7.62 is $6.00 a box around me right now at the local small stores for Wolf Mil. Classic. I've been looking online but alot of sellers are priced at $249 for 1000 rounds. That's WAY too high and I'm hoping the price will come down after the a couple of months. In the mean time, AIM surplus has HotShot 700 round cans for $139. I bought one a couple of weeks ago and have two more coming. They're so backed up with orders though, they told me they can't ship my order for at least two weeks.
Check Classic Arms, they have a pile of 7.62 as well.