I think that cab is probably a 1000S and the crossover is/was for the LE100S driver. That cab originally came with 2 D130F/D15S and the LE100S, maybe somewhere along the line the cone transducers were replaced with D140Fs and the compression driver was removed.
The head is the right era for the cab, but as you mention seems cleaner. That isn't real unusual; a lot of times the heads were treated with more respect than the cabs while on tour. Those big, heavy, awkward 2000S/1500S/1200S/1000S cabs took some mighty abuse from the "help".
It's a shame that rig can't talk...