Any ideas what this machine was?

Back in the early 80s, i worked as an assembler programmer for Reuters in London. I was involved with maintenance and development of software on two platforms - one was the PDP11, but the other was a much more obscure machine and i can't remember the name of the manufacturer. These machines ran IBM 360 machine code and we did the development in 360 assembly language on an IBM 370, which was later upgraded to a 4340. Recently i've been trying to remember the name of the manufacturer of these machines, but i just haven't got a clue - although i'm sure i'd recognise it if i saw it. I've looked through computer history sites on the web, hoping i'd come across the manufacturer's name and recognise it, but i never have. So if anyone knows, or can give me any clues, i'd be grateful.