My employer has only recently taken off sale a re-shelled 1980s Object Pascal application that needed direct serial and parallel access and we were able to provide machines that handle it and the various peripherals perfectly well. Intel Reference boards (which they're withdrawing for PCs sometime soon unfortunately) and Startech PCI-E cards for the ports. I think the boards even have a floppy controller although the need for them was finally removed by an upstream supplier buying some CD burners a few years back.
Something written to work on 1987 grade hardware can sometimes run faster than intended on a Core i7, though.
And my family doctor just dumped their old version of Wolf Medical to a new version, total cost for 6 computers? $118k.
I am definitely doing this job in the wrong country. Think our sleaziest salesman would have trouble getting more than $40k CAD for a similar size practice before financing costs including manually-assisted data migration from whatever existing system they were using.
The only systems I run in to that are stuck on XP or below are some Win16 apps. Would consider seeing if they'd run on ecomstation to have a less easily attacked (if only by rareness) system if they weren't competitors systems. Our own Win16 and DOS applications were borked in to running on Windows 7 and a brief bit of playing with one of them on Windows 8 was succesful too - but the last one to be withdrawn from sale was in 2008.
To be stuck on XP you either need to have been extremely unlucky, or be using something ancient and likely unsupported. And if a normal upgrade for an opticians is $10k, we really need to move markets/country.
"Been through Hell? Whaddya bring back for me?" -- A. Brilliant