Wow, that is a find. Hope it didn't cost you your right arm.

FWIW since this thread started I did find a Striker, and rebarreled it to 444 Marlin. Shoots and functions fine, but I did have to open up a .473" SA bolt head to .521" to get it to work perfectly. Easy to do with a lathe, and any machine shop should be able to handle it for a couple of bucks in a bout 10 min.