McMaster-Carr did have fully threaded, M10x1.5, 40mm long, zinc dichromate 12.9 steel 17mm hex, hex head bolts, which I was going to order due to their 170K PSI rating.
I still may if I can find matching washers big enough to prevent the hex corners from digging into the (not sure what grade/Rockwell aluminum) alloy end mounts of the Swave brace due here tomorrow.
I will look at the brace end mounts tomorrow and see if there is enough room around the bolt holes for some 30mm washers to use under hex head bolts.
(
Why I was drawn to the round shaped head, stainless Torx bolts I got, along with slightly larger Bumax 88 washers to help spread out that torque load over a greater area, and prevent that bolt top from digging into/'cold-forming' said alloy side mount.
)
I did not see
any; A286, 17-4PH, or zinc flake high(er) strength bolts, nor any flanged bolts I could use due to them not even offering some of them in ANY metric sizes at all, let alone in the one specific for this application, on McMaster-Carr's site.
They did have a Bumax 88 material option in this size, rated for 110K PSI, and supposedly more corrosion resistant than 316 stainless.
Maybe I should have gone for those?