what u mean by anti oil? just look for a sp with excellent oleophobic coating and it will solve your problem.

Oleophobic coating is a layer of coating on the screen protector which helps to reduce the fingerprint marks left in the screen. Even if there are marks left on the screen it will be much easier to wipe them off compared to normal screen protectors. Also the oleophobic coating will provide a very smooth feeling on the screen protector

I dun think there is any such service to coat the screen protector which originally does not have the oleophobic coating It only comes precoated on the screen protector. All glass screen protectors (even the cheap ones) have this coating applied on it, its just the matter of how long the coating can last. U can find these in most phone accessory shops or u can get one online

Currently the coating only available for industrial use. And not available for consumer use yet. There are some seller who applied this coating using mist, but unsure how long can last. Here's also liquipel, but if u google, there's a lot of complaints on it too.. Not working too well I guess..
Yea... +1 with bro dino89. It's better to get a sp than to look for the coating, however, like what bro dino89 said, depending on the brand/quality of the sp, the durability of the coating varies from 1 week up to 6 months  or even more. Choose wisely.