Hm, is there an archive of old versions of units.dat anywhere? Occasionally units get deleted from it - I used to keep old versions but I'd forgotten about thi

Hm, is there an archive of old versions of units.dat anywhere? Occasionally units get deleted from it - I used to keep old versions but I'd forgotten about this some time ago and haven't done so in a while. (Also that was several hard drive crashes ago so I no longer have the copies I made.)