I've seen the diff dirt cover rings on one of the ebay stores for a couple of $, so they might be available in the uk in a few months for a tenner
I wish they would release all the hopups in one go, getting everything in dribs and drabs off ebay is costing me a fortune in postage!
I need a new body shell as well... the back of mine is starting to break up (again) despite being patched up with shoe goo...
-Steve