mrbigh, there are plenty of deals on ebay, here were TWO 450 amp 6 pack mods for $63!!! I blew it there, just one would have made a nice xmas present.
Two Fuji 6MBI450U4-120, 1200V, 450A Trench-FS IGBT's NR - eBay (item 320454093633 end time Dec-02-09 15:59:33 PST)
And you can always grab 3 dual IGBTs, could make 600 amps worth for an inverter for about $100 without trying too hard.