I know people often say that compensated outs have no balls, but are you saying yours DID have nuts, and now they're gone?
Maybe those big nuts were just for show, to compensate for the jack's output, and now your amp is just more comfortable with itself? I mean, it IS the compensated out.
It does appear your amp is gay though. The outputs have had their nuts removed but all the inputs have nuts right on their openings.
Try your local electronic parts store. You'll probably have to buy a complete jack socket but they're probably only a few quid each. Just look for jack sockets that look the same, and have the same kinda nuts. They're the same as a lot of other pedals jacks (like my fuzz pedal, and wah's).