CPB, Find out what era they are, whether Proto 1, 2 or 3.
The tether and operating systems are not interchangeable, finding a GN A unit might not be easy, but another road name is an option in that series. Swapmeets are great places to check, as are Ebay, Trainz Auctions and the For Sale or Trade section on here. What you have are not powered and need the power A unit to move. They will run behind a Lionel or Williams engine though, and those are much more available than an MTH one. You would probably not get the sounds unless had them worked on.
