A true Target Trigger is .500 wide. It is wider than the trigger guard and, therefore not suitable for holster carry. .400 is the width of the trigger guard and came serrated or smooth called a Combat Trigger. Standard triggers were .265 serrated and the newer models are .312 (I think) smooth.
I looked in my parts box and I have 2 .500 Target triggers. Both were fitted to target guns used for Bulls Eye. If that is what you are looking for, I can send them both and you can pick the one you want. One thing, triggers
Do require some fitting. Single action is the most critical and single action is what the Target Triggers were primarily used for.
I am off for tonight so think about it and e mail me if you are interested. (I can also fit a trigger
)
Gary