The first thing I would do with that mess is take it apart, completely. Then sand blast the head and the valves and see what you really have. I have salvaged some really horrible looking heads and valves. Honda valves are amazingly good. I bet that after a good cleaning you will be able to cut good sealing surfaces into the seats and lap in the valves.
Ken
AHRMA 412
Vintage racing - old guys on old bikes
Ken
AHRMA 412
Vintage racing - old guys on old bikes