I am not sure what is meant by no factory support on the older models. However, I picked up a NYPD M64 2" from a friend awhile back. It had the bobbed hammer, and was double action only. Looking on the factory website, I decided to ship it back to the factory, with a detailed letter, requesting to make it more original with a standard hammer and single/double action. A week or so later I got a call on my cell from Springfield Ma. I immediately suspected it was the factory. Taking the call, I spoke to a guy from the shop who advised they no longer made the hammer for this gun. I told him about my decades long relationship with S&W, the models I own, the revolver and 3rd gen. Armorers schools I had attended when my hair was darker. He said he would see what he could do-with no promises. I told him thanks for the call, and about 10 days later the UPS guy comes to the door at my house, and had a box from 2100 Roosevelt Av….it was the M64 2" with a replacement hammer and trigger! The invoice said the work performed, and "no charge, customer warranty replacement". I suspect I got lucky!