“Deutcshe lichtbild 1962” published in 1961 has a advertising of “Praktisix”. This has a winding lever stopper. So, I think that, about 1961,change from “Type1”to“Type2”.
Early “Type 2” has a looks like top plate to “Type1”.And early model’s film winding point is made with only metal. Later has a leather cap. And,able to find other variation in “Type 2”.
The “Praktisix” is made by KW. Waist position finder has “KW” logo. Early model is engraved, Later model is printed it.