Are you “local” then? I am in North Cumbria near Cockermouth
Interesting I was not aware they had changed the design Is the grism holder threaded now?. I have 4 grism holders (the one from my original beta model ALPY 600, the one I used to build the ALPY200, one I got through the BAA supported program and one I bought a few months back for another experiment.) All just have a plain barrel with stepped groove for the grub screw. This is the component I mean
Cheers
Robin