It is dangerous to guess which lining that is, but Safetek sells a very large amount of ScanPac product, so I would guess it is GGW (Green Gripper Woven). I had a pair of shoes lined recently and it was $89 for the pair, so that's a good price. I was required to use stock shoes, which is a mistake. The thicker shoes are a real help.
I found that one had been flattened after it was returned. You have to measure the length of the shoes carefully. If one shoe is longer than the other then the long one has been flattened. It gets longer when it begins to collapse in the center. If both shoes are the same length they are probably both flattened.
If you reline a flattened shoe it may have the effect of ratcheting up the force on the shoe.
I don't think that the worn pivots will help much. Floating shoes usually only float in one direction (toward the drum.) Worn pivots may allow the shoes to move away from the drum and reduce the braking or increase the lever travel. I believe I wrote about making the 7" shoe float by using Triumph shoes with a single pivot. I have not tried it, yet.
I think that grinding or cutting back the lining is a good way to tune the shoe assuming you can remember the measurement of the tuning for the next time!
David