556 Patrol Spring Specifications

So 1 year ago I sold my 556 Swat Patrol essentially due, at the time, not realizing that 55x pattern rifles are still manufactured overseas and parts can still be imported and not wanting to keep a rifle I couldn't fix. Well yesterday, I happened to receive another 556 Swat Patrol as a gift/compensation for helping my neighbor with some home renovations before he sells and moves out of country. I loved my rifle and I am viewing this as a sign that I should probably keep this one. My only hold back is that, as far as I am aware, the short piston system was unique to the patrol and pistol models, and that sourcing replacement recoil springs is a little tough. However, I found a spring manufacturing website that offers over 100,00 springs of various sizes, strengths, metals, etc. I figure that before I decide to sell this gift, I'd see if I couldn't at least find some replacement springs there. If it works, yay! And if not, oh well. What I was hoping someone would have is the specifications of the short piston braided springs, or knows where I could get that information.

Specifically I need (in inches):

Outside diameter
Rod diameter
Free length
Rate (lb/inch)
Solid height (compressed length)
Wire Diameter
Material

This particular rifle has the braided spring, but I don't see why a single core wouldn't work or be better. This is probably a shot in the dark, but I don't want to keep a rifle that I can't fix, no matter how bad a** it is, and the recoil spring is the 1 thing that I just can't find.