Wow. That MRC Tech II has lived a hard life. While the main concern is the wiring from the 110 to the transformer and the condition of the windings on the transformer.
I'm not sure I'd personally risk it as you can find those for next to nothing these days in almost new condition. However, looking at your photos the chord looks like it's good shape. The only question I'd have would be the windings. Since these have overload protection you could likely plug it in and see if it pops the overload switch. If it doesn't, you could test the outputs at the various posts with a multi-meter and see if they are in the range of the posted voltages or if it is even putting out any voltage. I might do it outside away from flammable objects though!
Generally, these are really reliable. I have several 2500s, a dual throttle 2800, and several of the older gold top MRCS and they all are very robust. However, they haven't quite seen the abuse yours has. These were the go-to throttle packs of the 1980's for HO and N layouts.
