As soon as you posted the ring I gave you the parameters to use when searching (80 res, 50 life, some phys dmg). Clearly you didn’t use them (or you used 25+ ALL RES) otherwise you’d find as many rings as I did, which is enough to get a ballpark value.
The reason you got 10c is probably because the guy needed those specific resists and was willing to pay a few chaos extra, instead of shuffling the gear around to patch the resists around a dual res + life ring that he could’ve bought for 2-3 chaos.