[rescue] using type 4 keyboards on usb?

[Arthur Wouk]

after switching almost exclusively to type 5 and type 6s, i recently
returned to a type 4 used on my ultra 2. it is a lovely keyboard,
and i have a few more good type 4s. i also have a couple of mac G4s
and a couple of intel machines running linux/xp which i use various type
5/6s since i hate any other keyboard layout than the sun layout.

is there a converter which i could use to convert from the sun din
connector to usb and attach the other type 4s to the non-sun machines?