If you don’t have a datasheet, then this is a reasonable method:
One thing I forgot to mention is the calibration of your printer.
If you make a printout for bigger parts, this may become a problem and it helps if you can calibrate your printer by figuring out separate scaling factors for the X and Y axis.
With a bit of luck, then Yamaichi makes 3D models available of their test sockets as .step files, and you can import it in Pcbnew and use the 3D viewer to see if it fits.
With the search below, there are quite a number of results that pop up:
Or search and/or mail the manufacturers website directly:
Mouser apparently has some ECAD stuff available, and maybe you get lucky with sites like snapeda which has footprints for lots of weird footprints.