I also remember Ann uses that trick and has a quality supplier.
I still do that: the splendid Vested Interest vest (which was custom-made for me with huge pockets that are big enough for a 70-200mm 2.
is still in excellent condition after some nine years of use.
Unfortunately, the Vested Interest company itself (they were part of Storrie Parachute Works in Denton, TX) seems to have closed its doors and it's domain name is vacant.