Suzuki Samurai Transmission Tailshaft Bushing.
This is the bushing that the intermediate driveshaft rides on when installed in the back of the transmission. If your output seal continues to leak and you are sure that the intermediate shaft is in good shape then it is time to replace the tailshaft bushing.
This is not a factory part and is not made available from Suzuki. This part requires the use of a press to install. Once installed it also requires the use of an adjustable reamer to finalize the size to your output shaft (measuring out the outside diameter of the shaft will help determine the reamer size).