First off, unless you have some crazy Rem 700 SPS that I am unaware of this thread doesn't belong in the Semi-auto sub-forum. Been a lot of irrelevant posts lately and the carelessness is wearing thin on some of us.
As for the scope, distances you shoot will be short and the bullet drop significant. I won't specify brands but I recommend looking for a variable power scope in a lower magnification range such as a 1-8x, with fairly course adjustments such as 1/2moa or 1/10mil. Adjustments in the 1/8moa range are good for benchrest guys that don't deal with targets at varying distances. On a sub-sonic gun they mean a lot of clicks to keep track of and more time dialing. IIRC 1/8moa adjustment scopes usually have less overall travel too so with your sub-sonic rounds you will be limited on effective range to be able to dial. Or just get a graduated reticle and get good at holds.