A quick update on this, I found the part I was looking for by looking up the motor
for the GenSet and then finding the alternator
for this GenSet is a Kubota 10.5 hp Diesel
Here is the search that finally got me to the part I needed.
Kubota Tractor Alternator 10935N, 6C040-59250, 6C040-59252, EG67
Hopefully this helps the next person looking for:
Also, I had several people on a local Facebook page tell me they had bought this part from an Onan dealer and it was $300-$400 in the past and recommended I call them.
I found the part on several sites anywhere between $49-$80 with free delivery