The hits keep coming with this mower. I removed the seal and the dimensions in mm are 34.925X60.452X8.00. Brought it in with me to Napa and no joy looked it up online and can't find any metric seals that even come close. Looks like its time to rig something up.
"Bush Hog" is a company. They make rotary cutters, wing and finish mowers. Many people just use the name bush hog generically. I have a "Bush Hog" RDTH-72 finish mower. Sorry, I don't know if yours is a Bush Hog brand.