Slant six head

I bought my OS valves from Oregon cams when I had my cam out there for a regrind. As I remember they were a buck or 2 each cheaper than Hughes. I don't remember the brand of the valves they sent me. Might have been the SI brand, I've since heard may not be being made any more. Stock /6 length and stem diameter
Did you use valve guides if so what material because i see iron valve guides for sale on rock auto but i have seen people talk about bronze valve guides being the way to go.