El Rico

I've got a 1995 ls400 with 78,000 original miles. It began stalling out after exiting the highway after 11/2 - 2 hrs of driving. This is within the last four months. I checked these posts and it seems that the ECM is the problem. I also have the 40 mph rough engine ride. Is there any suggestion for where to buy ECM. Dealer cost is whopping $2200 plus tax. Other than that car is just a beauty.;Help!!!!!!1