Would you believe the local Toyota Dealer will not sell me just the spindle. If I want it I have to buy the entire assembly. As far as I know the hub,brakes, housing, spindle. $1100.00! Screw them! I had a bright idea last night. I remembered seeing a lot of Campers on Toyota long beds with dualies. I joined the Toyota RV site on yahoo and explained my problem. I have already gotten about 12 very helpful emails from nice people plus Junk Yards that have parts for the dualies. I may have found a spindle. Next week my mechanic will pull the wheel again. I will take pictures of exactly what I need and we will measure it for a speedie sleeve then decide what how we will fix it. Thanks for all the help guys. I will let you know how it turns out.
Toyota won't sell you a rear axle spindle because the spindle itself is part of the axle housing- it is not removable like the front axle. You would have to buy the whole axle.
This is a Land Cruiser axle, but it's very much like yours- the rear axle spindle is welded to the axle housing- non-removable- and next to it is a front axle spindle, which bolts to the front axle. They are not the same- the front axle spindle is shorter than the rear spindle.
Here's what you're looking at- it's a Dana axle, but the same applies to your axle.
It seems on your truck where the seal rides the surface is worn out, which is what happened to me. The seal in the back of your hub no longer makes good contact on the surface, the seal surface eats the seal, and the seal leaks.
(The old seal surface is just sitting there on the left side of the photo as a reference.)
I don't remember the size of the speedy sleeve, but I got it at Napa. It wider than the original seal surface, so once it was installed I cut it down with some tin snips and filed it. It worked great.
And sure, the axle was rusty and pitted- that meant that the axle just held more grease.

The speedy sleeve was very snug against the axle, with no play.
The speedy seal cannot be more than $60. A whole new axle, even from a junkyard is going to cost a whole lot more, and who is to say that the seal surface won't be worn out? Unless something else is buggered, I'd replace the rear bearings and seals (since it's all torn apart), get a speedy sleeve, reassemble, check your brakes and drive away.