Ive seen these up close at beaulieu autojumble in the summer, theres always a lot of turn of the century bikes for sale, and just pre war.. and they look amazing on those. Think they were selling them too in different shapes , sizes, qualitys, colours all sorts... i did pick up a leaflet but thats long since lost...
But the guy selling them also had alot of other handmade stuff and he had some woodcraft tools so i think he made them./.. they had a british van too so possibly being made over here as well?