If anyone is interested, here is our cad/blend file for our handheld cross-polarized scanning rig with the Elinchrom ELB500 kit: https://blog.polyhaven.com/polarized-photogrammetry-rig-for-elinchrom-elb-500-dual-flash/
It's a bit more capable than our AR400 rig, but also much more bulky with some quirks of its own :)