Thanks etigge for the advice. Saw the freewheel 8 speed on taobao too. Was thinking in this direction as it should be the cheapest. Might give this a go. If u want to let go the items cheap, I might consider too.
At the mean time, do I need to change the chain as well when going to 8 speed?
What's the approximate cost like for doing this upgrade?

There is a group riding every wed night starting happy garden, to summit n back.

Bike with internal hub can shift without moving. Won't damage the hub gear. It's one of the advantage of hub gear. Ie, when u reach the traffic light, u can shift to lighter gear to start moving, if normal gear, u have to down shift first when reaching traffic light, otherwise u will have to pedal harder to start moving.

Bicycle accessories are quite pricy sometimes.
Btw, mbax, can u share with us here, how do u buy from taobao? Do go through agent or buy directly?
Any problem with shipping and custom clearance?
I might be interested to buy something from taobao soon. Thanks.

Thanks for your tips. Which agent did u go through? PM me k.
Need to mod eco c7.