I found both shafts on eBay a couple years ago. I made a mid shaft with a automotive CV joint about 6 years ago used it for a few years then bought the Deere one. Mine actually works better and I shouldn't have bought the factory one. Now I have 2. The one I made is up for grabs if anyone is interested in it? Local pick up in CNY.
I've tried greasing the engine shaft with a needle adapter but have had better luck removing the floor pan, rops and rear fender. I think I'm going to try getting to it again from under the tractor in a couple weeks when I'm on vacation. I'll let you know how it goes.