stepper motor specs question

We have a "Sanyo Denki" stepper motor/w encoder with motor part number:
103-807-07E2. This part number is probably an OEM concoction of the
motor part number and encoder part number. The encoder is not labeled,
and is damaged. We are trying to determine the encoder specs (ppr,
output, index mark etc...) Does anyone have familiarity with this part
numbering scheme? Sanyo Denki does not sell motors with standard
encoders, so they are trying to dig up the info, but so far, no success.
It is a six wire encoder. A,B,C channels. The -07E2 (for the encoder
portion?) has a familar ring to it, similar to Yaskawa's encoder
numbering scheme, but I can't find any info on it. The motor is about 12
years old.
ca