No affiliation-
I just saw this listed today, it looks like a decent old bike,
http://www.ebay.com/itm/Other-Makes-GAS-GAS-EC-300-Dirt-Bike-300-Gas-Gas-motrocross-/321564507192?forcerrptr=true&hash=item4adebcfc38&item=321564507192&pt=US_motorcycles
I just saw this listed today, it looks like a decent old bike,
http://www.ebay.com/itm/Other-Makes-GAS-GAS-EC-300-Dirt-Bike-300-Gas-Gas-motrocross-/321564507192?forcerrptr=true&hash=item4adebcfc38&item=321564507192&pt=US_motorcycles