Ivor I've seen them advertised somewhere recently whilst I've been sorting out new Brake hoses for my 999. I'll see if I can find it again.
Have you tried these people ?, they might be able to help. https://www.bikehps.com/acatalog/Ohlins-Forks.html Or, these people could definitely make them, https://www.fastec-racing.co.uk/
Not sure if that arrangement of radial 4 pads bolted to axial fork mounts would be any better than simply using axial 4 pad calipers? I had axial 4 pad calipers on my 916 SPS Bitsa and couldn’t really discern any difference in braking performance between those and the radial 4 pad calipers on my 749R.
Fair point, they came with a bike I bought and I used them as fitted, not sure if the mount holes line up without the brackets? Never tried tbh
Sorry Ivor, haven't managed to find the link again. I think it was on a forum somewhere, possibly Ducati.ms Although there do appear to be plenty of manufacturers about: These are priced well below what I believe a CNC company would charge for a pair of one-offs https://lastaccata.com/en/brake-caliper-adapters/radial-caliper-supports