Those are the early style of W2 castings. They are the "Econo" W2 heads that do not require rocker shaft blocks. As well as use regular height valve springs. They don't support the same high lift that the full race heads do. Hell of a set of iron heads though. As cast they flow more than any iron small block Chevy or Chrysler head.
Prices can vary. Demand isn't very high for those heads, as most guys these days are wanting aluminum heads.
For example, I scored a fully ported set of early W2 race heads with a port matched intake last year for $400. That was an exceptionally good deal and perhaps not a good reflection of their value.
Ive seen complete unported W2s go for $600-$800 locally. Online I've seen them similar to yours in the $1200 range.
