A few people have used Jerry at Northwest Connecting Rod - here are a
couple of good stories on oil pressure and rebuilds:

http://volksweb.relitech.com/21rodbrg.htm

(for a 914)
http://www.pelicanparts.com/techarticles/914_big_four/914_big_four.htm

I see Bus Depot has heads for $499:
http://www.busdepot.com/catalog.jsp?model=58&category=15

And here is the link to the GoWesty engines:
http://www.gowesty.com/Merchant2/merchant.mv?Screen=CTGY&Store_Code=gw&Category_Code=mp-eng-rbe

Andree