I’ve recently had similar problems with a couple of mounts and what I did was ‘phone around a coupe of local small engineering firms. It only took me three calls. The first was too busy but referred me to another who was at the time closed due to the virus, but is open again and can make piers. The 3rd could do the job I wanted which was to make an adapter plate for a Paramount ME after which he was able to make the Owl nest adapter to hold the EQ8 to a metal pier, which funny enough I’m putting that up today. He is willing to take on other jobs for me.
So I’d phone around simple plans or photographs to work from is all that is usually required.