AFAIK the only one you can't buy easily is 1.4 (which is the beta to 2.04, only distributed internally to CBM and also with A3000UX).
Even then, it's probably not worth that much, as there doesn't seem to be any software that only runs on 1.4, but never runs on 2.
Sorry. Not much of a market for ROM chips / Kickstart files.
