Considering the size and shape of the '71 endura, that might be a prime candidate for a fiberglass or carbon fiber replacement part. It certainly would be much easier to graph on than a 70 or earlier one, or the 70-73 F body ones.
There are some out there that actually restore endura bumpers exclusively, and you can purchase one already repaired and ready to bolt on and finish. Not cheap, but some of those places will give you a core refund for a salvageable one.
Remember too that not only Pontiacs came with enduras, so places that specialize in the other makes are potential candidates for repair.
I know Paul at Fast may do just a bumper specifically, you could ask him.
Places like Legendary and Restore a Musclecar might also know someone reliable that could repair one, they deal with them frequently.
There are also used repaired ones that are on eGay that you might be able to find, a little risky, but you could probably homework it and reduce the risks.
There is someone who is reproducing the 68-69 GTO endura bumper, OPGI sells them, you could find out who makes those, and maybe see if they can do a run of the 71-72 endura, but that may have a considerable lead time.
https://www.opgi.com/bumpers-hardwar...o-G240103.html
Places like Ultra-Carbon and Anvil make carbon fiber replacement parts, they may consider doing one for the 71-72 GTO. The Anvil one has all the brackets that house the grills and headlights for the 70-73 firebirds, as well as many other cars, so it is possible. Probably not a cheap option, but still an option.
https://anvilauto.com/pages/1970-1981-firebird-transam
https://www.ultra-carbon.com/product...amarofirebird/
If you plan on doing it yourself, load-up on homework before you dive in. Here is a pretty good place, Paul at Fast is a great resource, pretty sure he still lurks here sometimes, and SPI has a forum that is also a good resource:
https://www.spiuserforum.com/
These things are getting more scarce by the moment, as are the people who can properly repair them, it's a shame but the way it is.
Just throwing out options here....
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1970 GTO Judge Tribute Pro-Tour Project 535 IA2
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1971 Trans Am 463, 315cfm E-head Sniper XFlow EFI, TKO600 extreme, 9", GW suspension, Baer brakes, pro tour car
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