2008 Mitsubishi Pajero Sport - I only know (for Malaysia) that Mitsubishi Pajero, Toyota Fortuner, Mazda CX9 and Volvo XC90 are SUV with 5+2 seating. I'd say 5+2 as while you can fit 7 "humans" into such vehicles legally (as it only has 7 seat belts, anymore and it would be illegal) the last row of seats is more for children or small sized adults. I've sat in the last row before and although it is okay for short trips like fetching colleagues for lunch, I don't think it's advisable for a trip longer than 20 minutes carrying all adults -- not too comfortable and stable. If you really want to ferry 7 people more comfortably then you'd need something like a Toyota Estima, Toyota Vellfire -- that kind of size. So it depends if you're not fetching 7 people all the time your idea of SUV with 7 seater capability is fine, else you might need to reconsider to get a big MPV. I'm guessing you're aiming for SUV not MPV is because of the road conditions in the east? Anyway, I found one advert which is slightly above your budget at RM50k. It should be able to fulfill all your requirements. And the seller is located at Kuching too.

If you smell a scam better just avoid.
That's the thing about mudah you've gotta use it smartly to find genuine owners that wanna sell.
Other websites that require payment for listing usually means they are listed by used car dealers which might be crooks or not but usually used car dealers sell at a higher price than direct user.

I found two Toyota Prade 3.0 near your budget and location.
here and here.

I'm not so familiar with Landy Disco, does it have seating capacity for 7 people? If not you might want to consider 2003 BMW X5 which is going to cost just as much to maintain.

I'm not much of a Landy person so I can't really give you much info from my own experience. I'm not too sure about servicing in this car in east malaysia do they have authorized service centers or just cherry tree workshops, but Landy's are designed to be robust and older ones like the one you showed are pretty common so I guess getting parts won't be an issue. I do know Brunei has a pretty good Land Rover distributor and service center.

If you got any Bruneian contacts maybe you can get a used 7 seater SUV from there, your budget of MYR45k = BND15k should be enough especially for older models as cars there depreciate like a rock.

I'm not suggesting the illegal way which is why you need the contacts on the Brunei side.
I know it is as simple as going to Brunei, buying the car cash, all documents surrendered to you.
Then drive this car to the border, either Limbang/Miri.
Pay the tax on the Malaysian side which is Tax % * car value based on cash sale invoice.
Both together would be cheaper than cars in Malaysia (many used car dealers in East Malaysia do this).
The problem is everything is deal using cash.
But I'm not sure how the registration on the Malaysian side works, which is why Bruneian contacts are important.
This is for 100% legal cars not like singapore logocars or clone cars.
Because I have colleagues working in Brunei that buy cars there then move it back to malaysia legally, but SOP's change all the time so you need someone that knows how its done.
info

The TZ model with a turbo-diesel uses 1KZ-TE engine. I've done a little research here and it seems this engine and gearbox is quite reliable with very few problems if maintained properly, of course the usual problems of wear/tear due to age and need to change parts is common for any car, overall it is a good thing.

However, TX model which also turbo-diesel uses 1KD-FTV (D-4D) engine is the newer range of turbo-diesel using common rail but I think for our market the 1KD-FTV (D-4D) only came about when they launch the new Hilux, Fortuner and Innova but iinm our market only as the 2500cc (2KD-FTV). I did hear that initially there were some kinks in the D-4D but by now it is a reliable and stable engine choice for Toyota fans. Further reading here.

Also remember when it comes to turbo diesel or diesel injectors like spark plugs are consumables, they are required to be changed. The frequency of the change depends on the diesel quality, for Malaysian dirty diesel the price to pay for that crazy high above 700km per tank mileage is of course injector kaputing earlier than manufacturer spec. Factor in injector cost + cheap diesel + high mileage per tank it still feels more worth than petrol turbo's.

I do know those two are quite expensive to maintain, never really bothered much with them.

2003 Kia Sorento - if i am not mistaken this car is also a 7 seater, i have a gut feel it is cheaper to maintain than the Volvo/Ford. Further reading here.

yeah mitsubishi's from that era did have such a reputation.
not only pajero but other models as well even the lancer.
there were stories that owners would make it a point to wash the car and clean the engine bay before potential customers come to view the car.
but it isn't really a bad engine design, replacing gaskets will of course fix the problem.
perhaps the gasket design isn't as robust as others but replacing the gaskets earlier than spec isn't really going to burn a huge hole.

however, before you make the purchase do check with the mechanic in detail as the gasket issue was my own experience with lancers not pajero's and the mechanic that fixed mine generally said this was the cause for most mitsubishi's.

generally you can't really mess up if you choose a toyota.
however, prado/pajero are two big suv's that are still quite well supported in terms of parts so i don't really see a big problem.