I've been getting into roll hunting in the past month, starting with nickels, dimes, and halves. I called around to a few banks to see if any had half rolls (most don't), and found one that had $410 worth. I went in, and took $250 of rolls. Got home, most weren't notable, one was even marked "1776-1976" and was all circulated bicentennial halves. Then I opened one, and saw a 1968 on top. Then I kept seeing more 60's dates. Ended up with 15 40% and 1 1964 half! Decided to go back and buy the remaining rolls. Only found 1 more 40%, but also got a 2007 D. Very cool, and a nice mix of dates in the 40% as well.
Congratulations! It's really hit or miss, and you did well. I haven't searched boxes in a while, but when I used to, I would either have a hot streak or nothing. I would think that smaller towns would be better; hand-wrapped rolls, etc.
Nice find. It's always fun to go through and find some silver. I have purchased a couple $500 boxes of rolled halves and they were a lot of fun. Keep searching.