Mount V-Rail on your wall by snapping or sliding one of these on each end of V-Rail and then screwing them into the wall. I used drywall anchors but you could screw this directly into a stud or similar. Once mounted, you can snap things on to it (e.g. see my V-Rail Spool Holder https://www.thingiverse.com/thing:3928465) or use T-nuts to screw things onto it.

I think V-Rail is pretty standardized so I would expect this to fit just about any you buy. But I don't have a ton of experience with it so it's possible that small differences could cause this not to fit. I used https://www.amazon.com/gp/product/B07GRL7FHJ/, which may not be the best deal / meter but it showed up in 2 days. :)