I was about to try rebuilding my two 8 X 7 garage doors three years ago, but found a Craigslist ad for 2 identical Wayne Dalton 8 X 7 insulated doors complete with all hardware for $100. The guy even brought them to me. My son and I installed them and the only thing that I needed to buy extra was the Weatherstripping. I later bought electric door openers and found that the doors already had the special attachment bracket on them, making installation of the door opener much easier than I had expected.
My point is that you should watch Craigslist and the other swap boards in your area for a while. You might find a deal like I did. He was converting his 3 year old garage into living space and no longer wanted the doors, so I got two almost new doors at a fantastic price.
Central North Carolina