David, that's a canvas case in the photo, the only leather is straps and fittings and also the carrying handle in the photo, these were common here in the UK
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Most companies bought their cases in from outside suppliers, in the 1920s The Altrincham Rubber Company offered cases in 200 different sizes and styles. This one is very similar to two Thornton Pickard canvas cases I have, the only difference is TP cases used a green canvas. The two companies had close links Altrincham Rubber Co being a sub-contractor to TP.
Typically a leather case was more than double the cost of a canvas case and the best triple the price.
Ian