Hi, long time lurker on here but signed up as I have one of these as well! Apologies for the extended reply.
Yes, they’re Canadian, I think from BC. They weren’t custom built but were produced in very limited numbers, hand-welded from 4130 double butted chromo. They were pretty expensive new, from what I remember about double the price of a DMR steel frame. Not many sold for that reason. I don’t know whether they had a UK importer, mine came directly from the builder. I think he stopped making frames in about 2007, and I’ve not been able to find contact details for him which is a shame, I’d love to get in touch.
They did 4 models. The early (which has a solid gusset, of which mine is), the SL, the FR and the DH. You’re right, yours is the FR but has the vertical dropout. Mine and others had horizontal dropouts but with a very effective integrated tensioner and hanger system. For a QR frame, the back end is almost as stiff as a modern through axle. The FR and the DH were both rated for dual crown forks and pretty much whatever travel you wanted. I never heard of a single broken frame. The early ones were black, with clear and white the other colour options. The very last were available in a lovely blue.
There’s not much of a modern following for them unfortunately, I don’t know any still going. Mine has been in my family for a long time.