Here are the two blades I ordered (part number for 3pk):
63502201270 3-1/16" Length, 1-1/4" Width, SLM Mount E-Cut Long-Life Saw Blade, Pack of 3 pcs
63502203270 3-1/16" Length, 1-5/8" Width, SLM Mount E-Cut Long-Life Saw Blade, Pack of 3 pcs
When I ordered from an online supplier, they shipped directly from Fein, so at least we know they exist in the U.S. You should be able to order them from your preferred Fein dealer. They should also have singles and ten packs, I believe.