Cast vs. Aluminum heads and bang for buck..
I’m going to try and limit myself to one post on this thread.
I doubt you’ll be able to get a set of used old iron cores completely refurbished, and updated with all new hardware, set up with hardened exhaust seats, bronze guides, with some minor bowl blending, etc........ done by a well respected machine shop/cylinder head service for under $1000.
You get all that with new import heads.
All new parts, stainless valves, bronze guides, hardened seats suitable for unleaded fuel.
In many cases, the import aluminum heads are less expensive than reworked OE iron...... and offer a performance increase.
The situation where this doesn’t always play out is when looking for replacement heads for the low performance OEM type applications.
Like a stock rebuild on a 318 2bbl, where something like a SM head isn’t a good option.