Had you considered a LS2 Iron Block. Yeah it is a truck motor but .060 bore nad 4 stroke and you got a 409 Cu In Chevy. You can get 11.3. to 1 or 9 to 1 for a huffer.
SLP makes it a 402 stoke bore short block for $3,500 and Several guys make the 409 Short, More sells it for like $8-9K
Its an idea!