I would call summit and jegs. If you can get b body stuff for that price, more than likely they will have a body stuff reasonably priced. I’d use 318 mounts with spacers (washers) before I would spend over $200 on ears alone.
Jeepers creepers those things are not the blade of grass keeping you from falling off the face of the earth for God’s sakes.
Ironically the A body with v8 k member is the one that apparently abaolutely noone makes. Infound the /6 to v8 and the small block to big block, but almost noone offers small block v8 one and the ones who do want 200$