No piece of any costume is "approved" by the 501st, let me just get that out of the way. Nit-picking, I know - but there's a big difference between "Approved" and "Approvable". Approval comes down to the actual trooper - each piece must fit you and and be correct to the rest of the costume and so on. Nothing is automatically approved by default.
That being said, the rubber chemical/dishwashing gloves are the correct approvable gloves at higher levels. At lower levels, including basic approval, there's a lot more room for interpretation in the CRL. And after approval, even Centurion, no one is really going to stop you from wearing different gloves as long as they don't take away from the overall look of the costume. The rubber gloves are THE WORST and super hot (especially in CA). I've literally seen guys take them off and pour sweat out of them. Nope.
The Nomex flight gloves are a good choice, but I don't much like the look or feel of the leather strip present on most of them, and they're still pretty hot. If I'm gonna go off-CRL, I want the most comfortable and utilitarian gloves I can get. I've been wearing these for the last year or so and love them. They're cheap, don't get very hot, I have great dexterity and can use my cell phone if I need to, and I just have elastic straps holding my handguards on.
https://www.amazon.com/gp/product/B06ZZ1J73J/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1