RE: Buckmaster, Fillfield II, or AETEC
All good choices... Right now I would go with the Fullfield II, because you can get it and the free 20x50 spotter deal... That is if you like the ballistic plex recticle. I don't personally like it, but a lot of people do.
I would also throw into the mix the Sightron SII, it is a great scope for the price.