Those look like the more desirable heads used on the Stage 1. They should fit at lease 69-70 455 400 430. I'm not a real knowledgeable engine guy. I think they fit a little earlier (1967) + later years, too...there were changes in them after 70, I think.
Those will bring more $ than the regular heads. You can modify the regular heads for the larger valves. I can't really say if those have been modded or not. They would have date codes on them, too. I could be wrong, it's easier for me to tell when the valves are in...there's like a fingernail width between the Stage 1 valves.
They are 70 and up. Rockers were lubed by the push rods . 67-69 rockers were lubed thru a passage in the heads . What is the Date code ?? Under the valve cover cast into the head is a letter and a number .
The heads are in the machine shop being assembled so I can't take any other pictures and the ones I have refuse to upload
If you want to see a pic of the difference...Google 1231786 head Images at the far right, the first row there are pics.
Based on this photo you posted there, these are non-stage 1 heads (standard 2.000"/1.625" valves). See http://www.buickperformanceclub.com/455hdcompare.htm for comparison. Devon