Funny thing about pumps. Can't tell who actually makes them anymore. The AC pumps I was buying no longer have "AC" embossed on the housings. I've had an AC pump, Carter, and Airtex pumps all sitting here side by side and once out of the box, you can't discern one from the other.
For me lately it's been a crap shoot which one will work anymore. Get one with too low pressure and it complains when it's hot outside plus it runs out of fuel with any aggressive driving. Too high and you have your experience.
The last 2 carter pumps I recently bought in the last month weren't any good. The first one only held 3 lbs. of fuel pressure. The car ran 20 miles and died. I warrantied that pump for another carter, this one held 3.5 lbs. of fuel pressure and I didn't even get out of the neighborhood with it, and it died. I bench tested both afterwards and they were completely dead. I'm assuming something inside just let go...diaphragm or??? But I wasn't impressed and didn't want to try another after towing the car back to the house 3 times in a week. They gave me my money back.
On my Formula that Bruce did a members ride on, I'm still running a "real" AC pump on it that has been on the car for 25 years. I'm waiting for the day it dies, but it's still kicking and holding good pressure. On my wifes Z I'm running a more recent AC pump on that one that doesn't have the AC embossed logo, so really don't know what brand it actually is, but it's been working perfectly for the last 3 years. I have a Carter on the Nomad that I bought 3 years ago and it only holds 3 lbs fuel pressure sitting there idling. Runs fine putting around the neighborhood but pressure goes to zero as soon as you mat the throttle, so it's going to come back off for something else when I get around to it.
So lately after my most recent experience I'm looking at switching all the mechanical pump cars over to a RobbMC pump. Doesn't look exactly stock but they are excellent pumps, they are rebuildable, and he sells the rebuild kits for $20 They come in a couple of different HP ratings and can be had with or without a return line setup, plus they are clockable. They are a 5 or 6 valve high volume style pump similar to what Nascar used to use. You can check them out here.....
https://www.robbmcperformance.com/products.html I've used them on customer cars and extremely happy with them.
If you're into the 100 point concour benchmark type of car, well then you're stuck trying to find a correct looking pump that actually works right and performs. On a couple of cars here I skipped the mechanical pump deal all together and just went to a Tanks Inc baffled tank and in tank electric pump setup, and hide the regulator. These setups have been flawless, hold perfect steady fuel pressure under all conditions, and has new car type reliability and quiet operation with the pump submerged in the tank.