A bottom half only case is worthless because they are supposed to be matched sets- sometimes you can get away with mix and match and sometimes you can't. A stock, unmodified head is worth 25-50 bucks and maybe you could get 100 for one cut and rechambered. That being said, if it is junk just laying around, I would trade for the Works- they are way better than the stockers, and you can still get them serviced or rebuilt by an independent rebuilder. Put them on and ride it, if you are not happy, sell them and buy something better.