Are you asking about two different rifles now? One you want a scope on, and one already has an Aimpoint, but needs a grip? Grips are easy- tangodown, magpul, etc. high quality for cheap. For the scope it would depend on what you want to do with the rifle.
-Is this a benchrest gun? Varmint rifle? Blaster?
-Used in daytime only, or in hours of low light?
-What range?