What Price Glory (WPG) is an online retailer of military gear. They have a selection of the authentic British Mark VII Gas mask bag. This is the bag used in the Indiana Jone’s movies. The first two Indiana Jones movies, Harrison Ford’s character had an olive green bag. The later movies featured the khaki color bag. According to legend, bags from Warring & Gilbow were used in the Raiders of the Lost Ark. The traditional Mark VII bag did not come with a leather strap. That was an add-on in the movie. WPG also offers a replica leather strap for your Indiana Jones bag.
Source: What Price Glory