Magnum exhaust manifold studs.

Ya, I looked also. not much for studs there. sorry !
Yep it's kinda nutty. There must be millions of magnum heads out there. What the heck are people using?
I did some google machine research, found out that stainless can be used for exhaust manifold studs. Although you must use stainless nuts and washers
There will be galling, at least that's what the Google gods said. So I guess galling isn't detrimental maybe unsightly?