I have one but honestly I'm not sure how the shaft seal is
Have you considered rebuilding it? Replacing the seals and the bearings are relatively easy with just a few tools that can be picked up at harbor freight or borrowed.
I just refurbished mine with new seals and bearings and it's running tiptop again. I wish I would of made a video because it was simple.
I have a brand new old stock dart must go make me an offer
Elliot. I can rebuild you old one. I have rebuilt several of my own and for others.
pm me if interested