I found that searching 6mm x 1.0 I found a british site.
Then remembered M6 x 1.0 threaded coupling worked out.
I went with Fastenal
I'll update when I get them in and try it out.l
OK. I didn't realize I didn't have enough room for them to screw onto the front mount bolts. Imagine each bolt goes around the down tube, not much clearance. But at least now I have wide 6mm nuts that I see could come in handy later.