gschuld wrote
2-If you intend to do a complete rebuild regardless, a 360 will likely be cheaper(better parts availability) and the 55 extra cubic inches makes a significant difference. The big valve 360/401 heads have much better flow potential as well.
This is the only part of your comment that I disagree with. Parts availability is not an issue for the 304, no there is no aluminum heads, but the small bore prevents for the most part any 360/401 heads from being used and the stock 304 heads will flow well past what most 304's will ever use. A stock rebuild on a 304 will cost no more to rebuild than it would for a 360, especially if the bottom end is left stock.
Pretty sure some others could shed some light on rebuild pricing with some numbers.
-Dave