[throwback]

Jaspar has them available. They bolt up to the old type 1 outdrives helmet heads. If your going to put a rebuilt engine in go to a 290 block same externally as a 250 but much better performance. Put a jaspar engine in my 76 v 20 runs well
One problem the intake manafold for the straight 6 is very expensive. Osco makes one but its around 6oo dollars