Re: Interestingly, there's a free "Express" edition for download
The OS2200 package can be downloaded to a UK IP. I know because I have it installed. I was surprised to find it included a pretty full set of software as well as the OS. For the Unisys/EXEC8 aware, you get the UCS compilers, no CMS but mini-CMS is included, DMS, TIP, ... all the normal stuff. This is the "Express" edition.
I feel like I'm in 1980 but my hair is still grey.