The shortblock..basic stock rebuild plus cost of block $1000-1200.

Rebuild kit $459
machining and misc and assembly. $3-400
cost of shortblock $2-500

Or take your chances with someones recently rebuilt shortblock.

There are a few that I know of..68-70 vintage ready to drop in.

If you want it installed, will be a case of beer extra.

You can find ready to hang exhaust systems, manifold back with or without x or h pipes for $250-350. Correct exhaust runs $1-200 more. Add $200 for splitters. check Dr. Gas, Edelbrock Pypes, etc.