I just picked up one of these bikes for myself, with the same crank. I think that'd be a good touring set-up with the granny gear.

First, you could try straightening things out a la Sheldon Brown's instructions. I think the ones for the spider might be the most appropriate, but you might be able to straighten out the tabs with a wrench. When I saw this, I thought the clothes pin idea was a good one - but have never done this myself.

http://sheldonbrown.com/straighten-chw.html

If you had to replace it, you might want to ask on the touring forum. I'd say a triple road crank, offhand - but some tourers still want a smaller granny gear than those have. I do think Sugino still makes a square taper crank good for touring. Any Japanese or American triple, square taper, crank should be the correct, JIS, standard (but you should check for that when you buy)

However, if you have to get new (or, new used), I wouldn't let the type of bottom bracket (e.g., square taper), etc. phase you if you can't get a square taper. Those trek BBs are standard and will take various cartridges and outboard bearings of all but the newest, raciest, $5000 carbon fiber bike bottom brackets. At worst, you'd have to get a new cartridge for the BB and those aren't expensive...at least not compared to cranks. Just make sure to match up the length (you can measure) center to center for crank arm length (e.g., 165mm 170mm, 175mm) - although, this doesn't seem to be a critical measurement from what I've read. 1 cm difference has never struck me as that large a difference compared to differences in human beings in height, leg length, etc.