The above, on the Royal H was just made from a spare fender stay. Survived a 20 mile trip with growler and a six pack in the handlebar bag. Most of the weight is taken up by the decaleur anyhow, the rack just keeps the weight off the wheel. I think I paid about $25 for a tubing bender, works fine.
Not exactly what I need as I don't have a fork crown mount. But this design looks awesome. Now looking at alu rod and the tubing bender.
The rack above is from Ren Cycles if anyone's interested. Nice but pricey!
https://www.rencycles.com/store/ren-gx1-titanium-rack-rack-only