Where may I find these for my bull barrel .22 pistol? I've seen beaucoup places that carry them for MK II's but not for the older ones. Thanks.

You may have tried this, but I would give Ruger a call and talk to someone in parts, as they might just have a pair. Also I can't remember the company that makes the Ruger "ivory" polymer grips, but they might also be a source. Good luck!