Any Eclipse head will work, just a minor modification needed to make it work (The 4g64 yahoo group has a tutorial on how to do it) The '94 GS head will go on directly but those are too rare. I'd suggest a 2g head as opposed to a 1g though. They can be had cheaper (just look for a crankwalk victim) and in my opinion are a better match to the '64 block.
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