I am in the same boat....though I am looking for a 742 case with 3.55s and suregrip.
I have found a 741 single leg, 3.55 but no other luck so far locally, where I can check it out some in person.....
Are you worried at all about buying a used chunk?
At $350, wondering if its worth the gamble/risk...To have a used chunk rebuilt is gonna be several hundred......add that to the $350-450 they are going for used, and you can pretty much buy one already built. ?????