I am also using a S&W 64. I have painted the upper 1/2 of the front sight with Green Sight Brite sight paint.
I had Ron Power (Power Custom) do his ball loc modification, as well as chamfer the chambers on mine.
I have been using Comp III loaders.
For a holster I am using a Lobo Enhanced Pancake with Inner Hammer Shield.
I have not settled on speed loader holders so far. The choices seem to be Blade Tec, Ready Tactical, and Tallon Tactical.
I may have Boomstick Holsters make them for me, as he is a personal friend of mine, and I shoot with him. He is great with kydex.
REVISED: I ended up going with North Mountain IDPA Compliant speedloader holders. I think I picked the correct ones.
I had a smoking run last Sunday at our local Sportsman's Club Outlaw IDPA match, and smoked the CDP and SSP guys with the old 64. I beat my own CDP score by 2 points. That will probably never happen again. A combination of the right stages, and not missing a beat with the Comp III speed loaders.
Good Luck with your 64. I am shooting my 64 more than any other handgun I own.
Like was said above with 38 Special Moon Clips you will be done with range brass. or sorting brass. You will probably end up going with Remington and or Federal Brass. The issue with brass is the rim under cut groove size. It is different on Remington & Federal, Winchester, and Starline. You would probably need to get the moon clips for the brass you are going to use.
CORRECTION: Looks like TK makes the Competition Clips for the K Frame for Remington & Federal brass only.
Looks like Starline for the 686 clips.
I have a 686 converted to moon clips. I also have a 625, 610, and 310NG. The 686 does not work as slick as the bigger rounds.
Also like was said above, moon clips takes you out of SSR Division.
Bob