Are there any other other tents which I should consider ?

If you go the tent route, I've had good luck with the Sierra Designs Lightyear 1 (3 lb.) Used it on several hundred miles of the GDMBR as well as lots of other locations/terrain. Roomy for the packed weight and fits me at 6'-4". I don't have experience with the SD Stash 1. Looks like the tradeoffs with the Lightyear are the LY gives about 12" more interior height but 1/2 the vestibule space and 3 oz. heavier. Interior height is nice when waiting out rain, etc., but I would seriously consider the Stash for the vestibule space if I were buying now. Stash is a few bucks cheaper but both are in your stated budget.

Wade

What is the approximate mileage remaining for the Sobo leaders? 

Kurt's latest spot stamp says mile 2220, so about 525 miles not accounting for alternates routes.