K-Pads will not work on the Lyn but will work on the lyn fury. Tez-O-Rings would work for the Lyn and K-Pads/CBC(888 sized) Pads, YYF Silicone Pads, YYJ Silicone rings would work for the Legacy.
Yes you can. I just put the o-rings from a journey in my legacy. By my calibrated eye ball, they do not stick up above the surface any more than on the journey, or a HM. If they are too much into the gap for you you could shim the bearing, or use a razor blade to trim them flush w/the surface of the shell.