For my college-level US history classes, I often bring in original items from various periods, and have several WWI era field gear items. I knew that the original gas masks are typically expensive, and the ones that are cheap are usually in BAD shape. So I set about to make my own. It can still give the general idea of an American-worn SBR without the cost, or the fear of damaging an original mask.
The mask part itself is stitched from heavy canvas, and I found some steampunk goggles for the lenses. The bag I made myself as well, although I still need to add the leather tab on the left si