I am going to answer the OP's question about which springs I use, but I am hesitant to do so. Let me explain why.
When I replace the springs in a revolver, I also go over the gun thoroughly to identify and resolve any issues which could affect reliabilty. This includes firing pin length, end shake, headspace, and any wear patterns or friction on the hammer or other internal parts. As one of many checks, if a frame mounted firing pin is less than .492" long, I replace it.
Also, if I want to improve the trigger pull, I polish the rebound slide and a number of other areas. Some of the areas I polish are specifically designed to reduce friction during the trigger return. Smoothing the trigger return insures that the return will still be very brisk, even with a slightly reduced spring. And a brisk trigger return is a requirement for me.
On some revolvers, I have polished the internals and kept the original springs. But I have not, and would not, changed springs without doing any polishing. If I open a revolver to improve the trigger, then careful polishing is required, but changing springs is optional.
Based on all of the above, I consider each revolver to be an entity of its own, and springs which work in one gun are not guaranteed to work in another. This is not a big issue, because I extensively test any gun with a variety of ammunition before I consider it to be trustworthy.
With all of the above stated, I have installed the Wolfe 8 lb mainspring and 13 lb rebound spring in a couple of modern airweight J-frames, and I have not had any misfires with factory .38 special ammo.
The stock mainspring weight is 8.5 lb, so the 8 lb mainspring is a slight reduction. The Wolfe rebound springs are a bit odd with J frames, because the factory J frame rebound springs are shorter than the springs for larger frames, but all of the Wolfe springs are the same length. So with Wolfe springs you use lighter rebound spring in a J-frame, but it is still the standard length. I have found that the Wolfe 13 lb rebound spring is noticeably lighter than the stock spring, but will still give a vigorous return in a well polished J-frame.
This spring combination gives a trigger pull of about 10 lb. That is by no means a light trigger, but it is a noticeable difference from the stock 12 lb pull. And if the parts are polished, so it is a smooth 10 lb trigger, it can feel pretty decent.
I should also note that you need to check the single action pull after you change springs to improve the double action. The lighter rebound spring sometimes makes the single action trigger too light and unsafe. Many people consider a single action trigger under 3 lb to be unsafe, and this something to consider whenever changes are made.
In closing, I want to mention again, that I am not saying that the springs I have described will work in any gun or are suitable for any purpose. I am only offering a suggestion about where you might start your own testing process. Anyone who wants to modify firearms needs to be aware of the risks and possible consequences, and test very carefully.
