I fired some pieces of pistol brass so many times that I've lost count.
That includes 10mm brass. I bought a few hundred once fired 10mm brass last year and have been firing full powered loads in it out my Glock 20. I guess I've loaded each case four or five times by now. Pistol brass has a very long life.
Unless you're over expanding your pistol brass, you'll lose it in the weeds long before ever wearing it out. Some of it is so cheap, that it almost makes no sense to purchase new, unless you're hunting dangerous game or making self defense loads. Like 9mm brass. Once fired is $4 per 100, new brass is almost three times more expensive.
Anyway, here's a company that sells once fired 10mm online. I haven't ordered from them, so you'll want to do the usual checks first.
http://seminolebrassandbullet.com/index.php?cPath=1_2
They sell it in lots of 1,000 for $91.80.