Unfortunately the manufacture no longer supplies the 6550502 toggle switch. I don't know how you would be able to repair it. You can keep searching online for the switch or find some one that might be selling their used BT2500 saw that you can part out.
The motor starts and stops like a car missing. Then finally stops completely. Tap motor housing with block of wood around where brushes are located and it runs until you shut it off. Then same problem. I see there are no brush replacements available.
The switch on my Ryobi BT-2500 gave up just when I needed the saw the most. I looked on the "net" and found a replacement one. The cost?? 35.00 !! For a switch??? They must be kidding me! A good quality single pole toggle switch with included on/off plate can easily be retro-fitted in the cover box. That's what I did. All's well now and the money I saved can be used for a new blade!!