My local gun club had an NRA Action Pistol match today for the first time. All in all it went fairly well considering that the match officials and the shooter were all new to this brand of competition.

We shot the Tyro Couse and the Practical Event for a total 720 possible. I managed an unexciting 551-14X with a S&W model 10 in production class, but enjoyed it a lot.

Are there any other shooters or clubs involved in this discipline?

I would love to shoot in matches at our club but they are all on Sunday & that is the day I'm busy serving. Sounds like you had a great time. I love the model 10.

There used to be 2 clubs in the Southern California area that held NRA Action Pistol matches, unfortunately they are no longer around due to lack of interest.
At one of the clubs Mickey Fowler and John Pride were regulars, both multiple winners of the NRA Action Pistol championship.
I used to practice with a NRA High Master several times a week when he was very active in the sport, the courses of fire really improved my trigger control and accuracy, and made a big improvement in my USPSA shooting. I shot a single stack .45 back then and made Expert class.