3500 Steering Box rebuild

After experiencing some odd tire wear on my very original '61 3500GT (AM 101 1512) with only 60,000 Ks on the clock, I decided that she deserved new shocks, and front end bushings. The tires only had some 10,000Ks on them, when the inside half of the tread went bald.
So here I am, replacing bushings, and shocks (most thankful to this site for advice, especially on things like that little hidden set screw for the lower pivot shaft). I'm performing this task on the running car, and had to remove the radiator btw.
While I'm at it, I figured that I should address my very leaky steering box. Therefore I am looking for some advice on this task, or recommendations for some one who may be able to do it. Are there seals that can be introduced these days? Are the bushing standard items? I just yanked it out tonight, but haven't dived into it yet, as I'm somewhat intimidated by it.
Many Thanks, RF.

 

so no one has been into the steering box? Does any one know the part #/use for the rubber donut in the steering column?
Thanks, RF.

 

Thanks Eugene,
You are always the helpful Guru. I actually have an input seal, and lower O-ring on order from MIE (they were out of the gaskets though). I forgot to order the donut, but will do so today.
I guess that there are just regular ball bearings involved, and not loose balls like the blow-up photo depicts? I've never really dove into a steering box before.
By new A-arm bushing went in quite smoothly with my simple Harbor Freight Press, and a touch of dish soap. I used a wooden dowel, close in diameter for the drift for both removal, and installation. (a closet poll, or broom handle)
Thanks for the input, RF.