Anyplace that fits can order a set. Senior flex is not commonly stocked at the box retailers. Titleist doesn't have deals with retailers to discount, so special order instead of off the rack is the way to go. Titleist will fit to lie and swing weight specified in the order within reason at no extra cost. The stock-stock AP1 shafts available in Senior are the XP-95 and Kuro Kage-65. There are other no upcharge Standard shafts listed in the Custom Order catalogue. I would have thought most fitters would have the 2 mentioned above, and Advanced Fitting Centers would have a couple of more for fitting. You also only need to buy the irons that work for you. If you like hybrids and Vokey wedges, you can just order 6-PW, not a 3-PW or 4-GW set. I use Titleist primarily because most companies don't supply materials to fit a left-handed senior. If you thought RH was hard to find...