While the Diamondback lockwork is similar to that in the Python, parts are not interchangeable because the Diamondback is made on a smaller frame. Some internal parts made for the Detective Special will work however. Do keep in mind that replacement parts are not a "drop-in" sort of thing, and require hand fitting by a 'smith that is experienced in working on these particular revolvers.
Most timing problems are more caused by abuse then wear, although it's a good idea to have the Colt factory, or some other qualified gunsmith do an occasional tune-up. Part replacement is seldom necessary.
The basic platform on which these revolvers were based were made from 1908 through the early 1970's, and extensively used by law enforcement and armed service buyers. Obviously if there was something seriously wrong with them they would have been discontinued long before they were. What killed them off was the need for skilled hand fitting, which today is far too expensive for any ordinary commercial product.
