Kris,
The 6.0 mast is "pre-bent" which means that the diamond wires combined with the raked spreaders initiate a constant bending force on the mast toward the luff track. The 6.0NA has two sets of diamond wires; an inner and an outer. The mast should show a bend but should not show a bend to the side. If there is a bend to the side, it could simply be that the diamond wires are too tight or loose on one side. If the bend is at the top of the mast above the diamond wires, the extrusion is bent (not good).
Pricing for 6.0's are all over the place. I bought my 1997 6.0NA with spin, trailer, large aluminum storage box, beach wheels, two sets of sails for $4k....but that was a steal. I think I've seen the 6.0s range anywhere from $3800 to $7000 used. Hard to say what it would be worth without knowing more about it. I usually start by figuring what the replacement cost is for things that need to be replaced (trampoline, sails, cordage, etc.).
