"Where is the best place to get parts for rebuilding the box ???"
Rocky, the bearings, bushings and the seal, if you decide to run one, are bearing supply items. Those items are cataloged by size and number if there is no legible number on your bearings.
When the sector housing bushings have been pressed in an engine shop can hone them to the EXACT size that will give a free fit to the sector shaft with NO play.
New sector shafts show up occasionally on ebay. New steering shafts with worm gears are very rare. There is a guy who advertizes transmission parts and driveshafts on ebay who may have the worm and shaft but his prices are sky high.
If you can use the information I will look up the number of the seal I used to retain gear oil in the steering box.
Also, those ball and socket tie rod ends have to go. They don't work properly even when new, too loose.
