You have a cool truck and here is some help pal.....
You can call these guys;
http://www.bpeheads.com/pictures.htmThey will sell you Manley or REVs. Talk to Mike, who built engines for Shelby. The REVs are forged in Argentina and are good enough to go in brand new Cobras, I use them a lot. The are a fair priced strong part. They stock 11/32 because the Shelby head changed from 3/8, to 11/32 a while back, with other tweaks.
They are also a good source for Manley
ALSO, we make a lot of valves here too, to any size or configuration, these guys have great pricing, they turn and finish the blanks/forgings. SI Valves.
SI Valves supplies a lot of people private label, good valves. They make stock valves, hi flow valves, NHRA legal valves,reduced stems,inconel,titanium. They have about a dozen versions.
http://sivalves.com/index.htmNow if you are trying to save money, see if a wholesaler among us can help maybe. Get a quote from BPE,Barry, Brent, Blair for sure. If you were close by, we could go get you a deal at lunch maybe, I am not here for business reasons.
The BPE guys port a lot of FE heads for a major FE manufacturer/builder too. Also for other real fast builds. Look at the names on their customer list, Louie Unser(Of the Unsers), Shavers,Shelby,Traco, Saleen, Arias and many more. And chek out the Drag and Salt cars they do, ton of Cobras, nice guys.
Nice work racing your truck,,,very cool !
Have fun