Thanks to all who have replied.
To those who suggested knee replacement surgery, it was discussed and is not needed at this time. The doctor said based on my films, he would have recommended it, but after talking to me, it doesn't seem to be necessary. (I don't have major pain - the pain I had after re-injuring it surprisingly has gone away - and it's actually getting back to moving normally most of the day now.)
I basically just want something for extra support (to keep my knee from hyper-extending and giving out), much like the thing at Wal-mart that ShowMama mentioned. I didn't really expect him to go all out and fix me up with a brace salesman. I'll definitely check Wal-mart to see what they have. $20 is much more affordable than a $1000 custom version of the same thing. Otherwise, I meet with the brace salesman next week.
pjaco, I will take your caution to heart. I don't expect to wear it all the time, only on long walks or bad-knee days. The idea was to be able to take long walks again, which I very much miss.