It may be parker #SK000092...
may be . Google that number and check with all the dist. and dlrs that turn up.
That motor looks identical to the ones on Wright standers.
Have you contacted Scag corp. ?
Having worked on many Parker wheel motors ( wright standers ) with leaking seals, I found that the majority of em had worn output shafts and needle bearings, which led to
internal seal failure. The outer seal is only to keep dirt from entering the needle brng which is grease packed.
Unfortuneately my 'puter took a dump on me ages ago and I lost all my saved info on Parker, We used a dist. in Maryland ( i think) who would have been able to fix you right up.
Start with that part number SK000092 and dig , dig, dig
Also google the scag number 483388
Good luck
This should get ya the service manual , it has a comprehensive parts listing also. :
TorqmotorTM Service Procedure - Parker Hannifin