https://www.v8buick.com/index.php?threads/billet-350-valve-covers.391220/#post-3456705 I can make you a set like this.
Sorry, I looked at the rest of the thread, let me know the price and if there is a wait time. Thanks.
Dont have the Poston ones but I have some extremely rare Kenne Bell 350 valve covers that are NOS I would sell. I was going to put them on a 350 Build but really happy with everything on my Disco car and not planning on building another 350 anytime in the near future so I am selling off all the 350 Build parts I have. PM me if your interested