I know there are tons but most of them look too thick to slip in and out of the loop on my sheath easily.
The one thing I'd steer clear of is a lot of knurling. So something like the Olight i3 should work well.
Harley's first hand experience backs up my educated guesswork. I don't use the Wave sheath very much, but when I did I tended to put my Leatherman Monarch 300 in the loop. Sadly now long discontinued. I'd guess that Leatherman would now want you to use the LED Lenser P2BM in there, but I'm not sure the focusing head wouldn't be a PITA when pulling the light out of the sheath loop.