1999 Subaru Legacy/Outback Wagon AT

Hello I just recently bought a 1999 Subaru Legacy/Outback wagon the chassis has only 119,000 miles on it with a completely rebuilt 2.5ltr DOHC engine which only has approximate 3200miles on it; and my question today is about 1300miles ago my speedometer just shut down going down the highway, but not for good it shuts off about 30% of the time and the other 70% percent it works just fine. I know and have been informed that this is a speed sensor issue. But can it be an easy and inexpensive fix? Can I unplug the plug on the passenger side of the tranny to clear up this problem or is it just going to get worse over time? :Roll: : I called up the local Subaru dealer and their parts counter said that the speed sensor was tied into the main wiring harness :( and the cost for it was approx $286.00 :shock: way more than I can or even want to pay @ this time. Isn't it too soon meaning before 150k miles for this kind of problem to be happening? Is there an easier less expensive solution to fixing my speed sensor problem? Thank you, peter parker