You can bend it back. You might want to take a wrench to it as well just to make sure it's snug. You could probably find some bad ass aftermarket shifter levers for that bike for cheap on ebay.
It all depends on the bike you get. If you get a smaller bore 2 stroke they last a long time on a top end, the bigger bores will need to be changed every season or every other. It all depends on the 4 stroke you get to, yamaha and kawasaki so far are the most reliable I have found. How you ride makes a big difference, if you race and have the bike pinned all the time you will have some problems, but thats what its like with any engine, trail riding is easier on the motor, but can be tough on all the other parts.
P.S. Warp 9 racing oversized shift lever, got one in not to long ago and haven't looked back.