Please check this out:
Single Action Shooting Society, SASS.
http://www.sassnet.com/They host a fastest growing shooting sports in US at this moment.
"Cowboy Action Shooting", to join you have to have
At least one single-action, fixed-sight revolver.
Ideally, you will have two six-shooters, since many stages are designed around shooting a double rig. Your revolvers should be in period-correct calibers, such as .45 Long Colt, .44, .44-40, .38 or .32, and you will need to be armed with unjacketed lead traveling less than 1000fps (the targets get harder to hit with holes in them).
Gun belt and holsters.
Most stages will require you to draw and re-holster at least one six-shooter, and besides, you want to look good, right?
or Lever-Action Rifle chambered in a pistol caliber.
For simplicity, most shooters stick with the same caliber as their handguns, and it's vital that the rifle does not produce a muzzle velocity past 1500fps. Many stages require 10 rifle shots in a row, so the rifle's magazine will ideally have that capacity.
or Double-Barrel Shotgun, without ejectors.
Most shooters stick with a shorter-barreled "coach" gun for quick handling, and many show up with a bandolier to hold the extra shells that are often needed on some stages. You are often knocking over fairly heavy steel targets, so though 20GA is acceptable, 12GA is more common.
and dress like a cowboy or cowgirl, cowboy hat and boot, etc.
I would be fun if anyone can host the kind of event in Thailand.