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Do you know anyone that can straighten bumpers in preparation for coating?
Maybe TriCity?
Keep in mind though that powder coating over chrome is NOT the proper way to do it, though lots of people do. I'm not one of them.
The absolute best way is to get that chrome chemically removed at a chrome shop first because it's faster and a lot cheaper than trying to blast it off, especially a good old triple plated nickel / copper / chromium job. Even trying to get a decent blast profile on it takes hours, and even then is half *** ... because any impact can take not only the powder layer off but the chrome layer as well. Then the elements get to work on it and before you know it, the whole job is coming off in sheets as rust forms in between. It's called "creep."
When that happens, it isn't the chrome shop whose reputation suffers. It's the powder guy who is rightly at fault for not doing it properly the first time by applying the powder onto a bare, impeccably clean substrate (the blasted bare steel bumper).
Put your chosen powder shop on the spot by asking exactly what prep your bumper will go through. If "I'll rough it up with a ScotchBrite pad" is part of the answer, you'll get exactly what you pay for: a half *** job.
Hopefully whomever you get to straighten them can also strip the old chrome off for you too. If you don't get it down to bare metal, you're wasting your money and tempting Fate that it's going to last.