My TMEC enduro is used as a daily commuter, and it came stock with a 17 tooth front sprocket, and 56 tooth rear. Even with the large front sprocket, it was still geared very much for off-road. The problem with these Chinese enduros as far as rear sprockets go is figuring out which hub these bikes were cloned from. The TMEC uses the same hub as several European 'motards' available there and not here, so I had to source my rear sprocket from the UK (after tracking down several online retailers in the UK and continental Europe who DON'T ship to the US, I found one!).
My bolt pattern looks similar to yours (the six bolt, with two near each other) as opposed to when the Chinese manufacturers made it REALLY easy and used to use the hub design of the 1979-1981 (don't quote me on the exact years) Honda XL185s. Probably other bikes, too, but I do recall finding numerous available sized rear sprockets on Dennis Kirk.com for a 1979 XL185 for my 2005 Jetmoto 200 enduro.
Looking at the photo, it already looks like there is a small sprocket on there. I would not touch it, to be honest, if it is already in the 40's. You can go smaller on the front for off-roading, which with these bikes means trail riding vs. any jumping. If you really want a 46, and your hub is patterned exactly like this, as is my TMEC (it will involve measuring and such), the smallest commercially available sprocket is a 48 tooth. I commute on mine, and it hits 60+ mph, but I still wish for a smaller rear sprocket, meaning it would be perfect for both street and light trails.
http://www.jtsprockets.com/catalogue/model/3328
Don't look at the front sprockets shown because our bikes use far more available Honda front sprockets (maybe XR200, but someone can fill in which one exactly), but the rear sprockets as you can see go from 48 at the least to 54 teeth. You will have to measure, however, because you might just have a whole different hub.