I and others report good experience with those from Richard Falluca, of Anitique Engine Rebuilding.
https://www.antiqueenginerebuilding.com/index.html
My understanding is that these are the parts that Snyder's sells.
Additionally, Richard offers oversize intake values (requiring also oversize valve seats, mandating minor block machining), which do not seem to be listed in Snyder's or others' catalog listings.
I intend no derogation towards Piranio's offering, I just have no experience or knowledge of them.