Well, since you are saying you will perform all the labor, and if the block, crank and rods are OK then the cost could run as low as around $1000 materials. That implies a used head but the chances of finding one that doesn't have cracks is very unlikely, as well as avoiding the infamous #14 head. This is based on a complete (loaded) head without having it skim cut for assurance that it is flat. These heads tend to warp and cause the head gasket to fail if not perfectly flat. You take some chances this way of course.
You may as well have a complete head job w/ new valve guides and seals and valve seats ground, that adds about $400 (plus shipping two ways?). If you wanted a new head it will set you back about $2K - last time I looked for one about 18 months ago that is what they cost I suspect the price is higher now. Adsit wants $1600 for a bare head reconditioned.
I am in process of rebuilding a 603 engine and may have a possibility of discount on a multiple parts order. PM me.

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