If making one for bushcraft I would personally make a few simple alterations to the traditional fishing type, I would have Velcro fasteners on the cuffs, the cuffs would be wide enough to roll up past your elbows, and Id have a zipped neck collar that zipped down quite low to about your stomach for ventilation. Designed for fisherman of course it was essential to NOT have any buttons etc (they catch and hold the meshes of a net hence apart from being a nuisance it can be extremely dangerous leading to drowning if one falls overboard if the meshes get stuck on the buttons) however for bushcraft use buttons/fittings are not an issue. I used to use a fishing smock (for fishing & netting) from an Ireland company which was excellent but am afraid I cannot remember the makers name.