Its made by Tamagawa, their logo is also on the inside of the encoder housing casting.

The encoder housing looks as if it has been designed specificaly for this motor so the motor could also have made by Tamagawa?

The wires are,

Black, Red and three pairs of coloured wires one in each pair is marked with a black line down its length. The pairs are Blue, Green and Yellow.

There is no model number which relates to anything on the Tamagawa website site, the number on the board which looks most like a model number is 6590-1815.

It also has the following code on the circuit boards UL NAS-85-v r09064NI