Domed decals is gonna be your only alternative for a one-off application like this, the doming resin can be applied over any decal material even digitally printed vinyls which produce some decent looking decals, the tank pads for example are domed decals. These decals can also be painted to achieve a more solid or metallic surface appearance (that of an emblem), any way you go about this it's gonna be a one-off custom application and is gonna be somewhat costly due to the time involved in the process, check around some of your smaller independant sign shops, they should have the capability to produce something like this for you. Maybe it's time for me to breakout my old doming resin kit and make up a batch domed chrome kanji emblems.