In these cases your best bet is to take it to a 'good' auto parts store and let them locate it by dimension. I utilize my local Carquest just up the road in Marlin, TX for example. The same folks have been running it for 40+ years. I can take just about anything in there - if they can measure it, they can usually get me a replacement. And if it's a lip seal they almost always even have it in stock. I know 'good' auto parts stores are fewer and much further between these days, but I'll bet you can find one. Good luck.
