My local shop sells both D'Addario and Ernie Ball 10-52. GC has them, too.
no ****. d'addario is my brand but my main shop doesn't have that gauge.
i swear i could find this gauge profile all the time back in the day. nowadays not so much. is it just me? or perhaps it's an 11 or 12-52?
These are "Light Top/Heavy Bottom" sets and they're still pretty common. A Google Shopping search for "10-52 Strings" returns hits for just about every string manufacturer you can think of. Elixir was absent at first, but a direct search for that brand yields a hit as well.