"How long would 10 lbs of tobacco last you?"
In his "The Ultimate Pipe Book" Richard Carleton Hacker provides a possible answer this question by stating, in part, that, "...there are about 30 to 40 pipefuls of tobacco in every pound (with a slight variance being allowed for pipe bowl size and the cut of the tobacco)..." Using 35 as the average, that means that each pipeful would be 0.457 ounces. Accordingly, 10 lbs. represents 350.1 pipefuls, that is if my arithmetic is correct.
For me 10 pounds of pipe-tobacco would last a long time!