HeavyArty
One canteen on right hip.
Marines typically carry two canteens.
This has changed with the widespread use of camelbaks.
François might be forgiven, the Belgies were still using M-1910 variant hook for their LBE into the 80s. Those hooks connect things at the bottom of the belt, and often at the top of the carried "thing." They can then bounce about.
The US adopted the slide keeper in 1956, which holds those items securely to the belt, and right at their centers.
Our CPT here could be using the extending strap on the UM-84 holster, which will get it neatly (if not obviously, the extension strap is narrower than the holster) under the PASGT vest.
[Bianchi also made a drop-leg extension, which gets the holster down to the top of the thigh pocket, and has a thigh strap to prevent flopping. I know of tankers who rigged that way, so as to not have the vest over a shest holster.]
If the CPT is a Company Commander (and especially if a Battalion XO) that dressing pouch is likely in the front pocket of the vest. Maybe. Perhaps.
Going around SWA without a canteen of water does not sound smart, but given the sculpt, I don't know how to fix it without a Farby. (Going to wager an IRL CPT would have bottled water in the other vest pocket.)