Found this brochure amongst some stuff a seller included when I bought a blank 540B board:

OSI - Space-Com.jpg

The seller's note says the board was purchased and shipped in the box he sent me from Space-COM International, which he intimated owned OSI at that point.

I've been trying to piece together OSI's history recently, especially post-Cheiky. It's pretty muddled. It seems to go sort of like this:

1982 - Bought by MA/COM
1984 - Assets/trademarks, etc bought from Bank of America by ISOTRON of Sweden (OSI or MA/COM went bankrupt?)

I'm not sure where Space-COM fits in. As the brochure says, they were producing a line of OSI-based systems under their own name. I've done some googling but can't really find anything. I hadn't heard about ISOTRON either until I stumbled across it in PEEK(65). The same publication in around late 1984 mentions some sort of 'near disaster' with OSI.