If your budget is on the lower end for FFP scopes, fwiw, I put a Vortex Diamondback Tactical FFP 4-16x44 on my young son's 6.5 CM, for approx $350-400.
Not a lot of use yet in the field, but no issues so far. It's been a good value, so far, and he's getting an early start on learning to use FFP.