I have some experience rebuilding a 4-cylinder, 4-stroke top end (a 1977 kz1000).
Look at the taper in that other cylinder to the left of the bent one. That taper is machined in there to accommodate re-installing the pistons into the cyclinder -- without that taper at the bottom of each cylinder's bore, it is difficult to get the pistons inserted into the cylinder so you can lower the cylinder onto the block. (I know this because the machine shop that did the bore job on my kz1000 forgot to machine a taper at the bottom of the 4 barrels. Still got the pistons in there, what a female dog that was.)
So it is hard to tell from your picture -- is the bent part 100% limited to the tapered part of the bore?
One thing you can try: take the cylinder to a machine shop and have them check it. Maybe, if the bend is in fact impinging into the piston's region of travel, the machine shop can do a 'bore' job by choosing a bore that is the same size as the cylinder so when they bore that cylinder, they will cut away any metal that is in the bent 'flat' part that impedes piston travel and the bore won't affect the good part of the cylinder.
If a machine shop tells you that is not possible, I'd say to see if removing that cylinder's liner and installing a new one is less expensive than buying a new cylinder (may not be, I'm not sure -- I've seen some pretty cheap cylinders on ebay in the past year).
