Hey all, I'm looking at the Gideon Hask build as well and thought I'd post a few measurements on his bandolier. I've done this with several different screen shots and always get essentially the same measurements.
I've done the ratio based on the original CRL belt for TIE pilots/officers at 2", and also averaged between the smallest and largest sizes mentioned at 2.5"
Taking measurements off of my TK:
The waist ammo belt on the TK is 3 5/8 (3.62" or 9.2cm)
The thigh ammo belt is 2 5/16 (2.3125" or 5.9cm)
You can see that with either TIE/Officer belt size we're smaller than a standard TK waist ammo belt and larger than thigh ammo belt.
The ONLY way I can make the bandolier fit existing TK dimensions is if we assume that Hask's waist belt is 2.75" wide, then we net 3.69" for the bandolier, which is just about right for a TK waist ammo belt.
Hope this helps.