The pontiac 350 has the same 3.75 stroke as the stroker chevy, just has a little smaller bore (3.875 instead of 4.0 )
Sounds like it just needs some tuning to get it right.
At the moment I have a 71 350 2 barrel in my 64 , and it has no lack of power.
itll smoke the back tire till its bald.
I would do some basic checking of the motor you have, it can be made to run.
You should be able to get decnt power from the 350 you have and not spend a ton of money doing it.
Fact is stranger than Fiction