Here is a 2nd source for the welded sealed back type, from I can see the quality appears to be there. I wouldn't use stainless into stainless, even if you're not cross-threaded, the binding can be extreme (even thread lube doesn't guarantee a smooth run in). I would probably use a 7075 bolt if I were to give it a go. Maybe someone here has 1st hand experience with them, curious what they think.
Stainless Nudge Bars and Over-riders - Car Builder Solutions - Kit Car Parts and Accessories
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