[herkyhawki]

Too much focus on "CHEAP". There is alot of labor involved, and incidental costs for gaskets, hoses, plugs etc when you replace an engine. The installation time and cost of these extras will be the same if you are putting in a junker or a solid rebuilt engine.
If you can't come up with an extra few hundred $ now to do it right, then what will you do a few months down the road when your CHEAP junker needs to be replaced again?
Find a good automotive machine shop and level with them that you need to get this done as inexpensively as possible and ask them to work with you. Many of these shops are hungry for business because there are so many"crate motor" dealers around now. Even though the shop would rather do full price rebuilds, many of them will also recognize the opportunity to win a customer that will come back with other business for years to come.