I've got loads of metal benders, tube benders and dies. they're handy things to have if you do fabrication of any sort. don't bother with a plumbers tube bender, they're not strong enough.
get a Hilmor conduit bender as they will bend steel tubing. for handle bars you ideally want 22.2mm (7/8") tubing die. but they're hard to find. you can get 22mm easily enough though. I have a spare to sell if you wanted to go down that route, would need collecting Sussex though as its heavy. otherwise you can pick them up relatively easily online second hand and best for a relatively affordable set up.
you will get people say they're not good for the job and to get some absurdly priced tube bender but I have only ever made clean bends with them with no kinks.
Vincent frame BMXs used conduit benders to make their frames and bars back in the 80s, I don't see a problem with it.
only down side is the dies are fairly large so you can't do tight radius curves but ideal if you want to just put a bit of angle in to something.
another option, you can get a compact metal bender with tube dies, I think you can get tighter curves on them but starts to get pricey with one of them. but they're handy to have for bending flat bar, etc