Douglas would build that contour in SS as well. Builds them for Mel all the time.
Kreiger won't in stainless, neither will brux, ironically based on kreiger's cold weather shooting liability/policy.

The Vx-r in 33mm will save you two ounces over the 40mm.
Figure if you're going "ultralight" all options are on the table.

Great build, thanks for posting!