The more I think about it I'm pretty sure the head I have might be a 250 head because the dome size compared to my original picture of my 500 head and the dome size of the head I have now. It also fits on my cylinder but my cylinder lip has like 1-2mm all the way around of over hang (where the head is to small to match up with the edges of my cylinder).

A 250 head will not fit the 500-bolt pattern. The outside diameter of the head gets smaller as the head gasket surface is machined.   Measure the thickness of the head where the head nuts seat.  A stock head is about .800" thick at this point.  I do not like to use heads that will be thinner than about .675" at this point when they are finished.

Small pits on the surface of the combustion chamber are not uncommon and are nothing to worry about.  The small pits are from impurities and gas bubbles in the casting.  Some head castings are worst than others. Occasionally we encounter a large pit that was below the original surface when porting a cylinder or machining a head..  Most of the time we can weld up the pit.  I have had to throw away a couple of heads that could not be repaired.

The pictures show some discoloration and what appears to be coolant stains or rubber remnants from prior usage in the o-ring grooves. “ Freshly" machined surfaces will usually have a bright shinny look and not stained or have the dull look like the head in the picture.