OK I found these. 400v and 400a for $133.00 each. They have a bunch of them. Looks like these are usable, except what are pins on the end for?
CHNsalescom Welder repair Infineon FF400R06KE3 400A 600V IGBT
600v 600a are either rare or horribly expensive. Perhaps in a few month Mouse will have them back in stock.