If you have a little money burning a hole in your pocket check out the DOHC 904 engine currently for sale on Ebay. Starting price is $50,000. This should be a plain bearing crankshaft (instead of roller bearing) two liter engine making about 180 BHP.
Of course parts prices aren't a consideration because none are available anyway, and they are a mechanic's nightmare for anything other than routine service/maintenance.
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