BillofRights

I have a 2005 Legacy Outback, 3.0 L Boxer 6. The cruise control won't operate becasue the CEL comes on and shuts it off. Dealer tells me code is P1844, which means a valve body in the transmission, and their estimate to replace it is $1400. My question is, is this a repair I should only trust to the dealer, or can any worthy repair shop handle it?