what kind of heads would you use?

Well, with the way your post reads, I would use the Indy's OOTB, lightly preped and cleaned up. Something the shop your dealing with would od. No real enhancement work, just good common sense type work before bolt on.

The heads flow preety nice OOTB , IIRC and could make some big power as is. I would go with the rectangle port and there intake.
I think there a set of heads than you can really grow with.