You can still get the large 5pin din connecting keyboards on ebay. Search for "G83-6414" for example.
But I think the 5pin to ps/2 connector may just be a straight wire through to the smaller connector, so you can reverse that?
Threw out turbo-xt motherboards well over a decade ago.
Still have a couple 16mhz 386sx motherboards somewhere that I cannot seem to make myself throw out because they worked fine, just (very, very) outdated. They are so tiny (1/3 board size) that they don't take any space to keep around.
Also have some isa vga cards somewhere - could send you one if you really needed. But the original XT also had an optional color card with composite out that could still be easily used today.
My memory is that the AT (and PS/2) keyboards shared the same signaling, but had different scan codes. So it wouldn't work to plug a PS/2 keyboard in via a DIY adapter.
But I think the 5pin to ps/2 connector may just be a straight wire through to the smaller connector, so you can reverse that?
Threw out turbo-xt motherboards well over a decade ago.
Still have a couple 16mhz 386sx motherboards somewhere that I cannot seem to make myself throw out because they worked fine, just (very, very) outdated. They are so tiny (1/3 board size) that they don't take any space to keep around.
Also have some isa vga cards somewhere - could send you one if you really needed. But the original XT also had an optional color card with composite out that could still be easily used today.