Front sprocket / EC300, 2009
 

Front sprocket is gradually wearing out.

Since it is difficult up here to find spare parts for Gas Gas, which sprockets fit the EC300 (I mean Yamaha xx, Kawasaki yy...)?

Is it possible (or feasible) to turn the current sprocket the other way around, as it is still in okay condition?

As far as I know there is only a crossover on the rear sprocket with beta I think.
It is not advisable to turn it round best to replace the whole set sprocket and chain. Not sure where you are based but motocrosscenter.com deliver to me within a week at reasonable rates (although you will most likely save on shipping if you can get the 520 chain locally)

No crossover on the front sprockets, but they're not hard to source (order it and rx in the mail). Few different brands available. Talon, JT, Dirt tricks, etc

http://dirttricks.com/shop/sprockets...ront-sprocket/
http://www.ebay.com/itm/JT-13T-Front...RW9rzU&vxp=mtr
http://www.cyclebuy.com/shopping/spr...m#Ironman_Info

Rears cross over with some older Italian Huskys.

I'm pretty sure T.M. en series fronts are the same.