The J frame mainsprings and rebound springs have generally remained the same over the years. Mainspring: part number 07104, and the rebound spring part number 03105. (Blue and nickel mainsprings are part number 05749)
There is a model 60 mainspring in my parts book with the note "NY", as number 07795. I'm not sure if that spring is still in use. Knowing New York, it's probably a heavier rated spring, although I've never laid eyes on one.
There are variables in the Performance Center J frames, which often (but not always) use an 8 pound Wolff mainspring. The factory spring is 8.5 pounds, according to Wolff. Also, you can easily recognize the Wolff springs because they are not flat ground on each end.