Seems like you have a pretty good combination for what you are wanting to use it for. My suggestion is to get a good set of aluminum heads that are not too big for what you have but are just a tad bit more than what you need. That way later you can step it up some more. You can get some really wonderful heads for what you're doing for less than the 3,000 you mentioned.
Do not under estimate what the 2 bolt 454 Factory block will handle. IT is strong. I suggeest to get a good steel crank of some sort and good rods unless you already have good ones.
For an application like you have, I like the Canfield heads, Competition Products is a good source for them. Talk with Butch Patterson. He is an engine builder too.
Ed