As John rightly said, Gerrit, the asbestos is not used as an insulator but just like on white gasoline lanterns helps the fuel to evaporate more evenly in the tube and also acts as a filter for the jet.
If you intend using only paraffin, you can replace the asbestos rope stuffing with brass (or copper) spirals like in the Coleman 249 generator.
Look after that gennie, they are virtually impossible to find.