The capsule chamber seems to have stress cracks but is intact.
I would look for diaphragm cracks or tears, through the screen (end) with a microscope or magnifier.
They are very fragile, 6 microns thick. Don't even think of touching it. The tension is fixed on the ring.
Either it has lost tension or small chance the electronics are might be damaged, here are a few voltages to look at. You could measure the capsule capacitance, this schematic mentioned 41pF.
More information on the MXL603s capsule, and teardown pics:
http://recordinghacks.com/2013/01/10/dissecting-the-mxl-603s-capsule/"Be aware that this disassembly will probably render the capsule unusable." It must be dust getting in.
This low cost mic gets lots of mods, from better capsule to better capacitors. The through hole PCB is worth keeping.
I did not see much for original spare parts for sale.