Well, I think I may have found the car (actually, someone on another forum pointed it out); a 1979 Ford LTD II. It has the right handles/keyhole combination, very similar wheels, and, most telling, has the exact same pinstriping pattern on the side and the hood. They were only produced for 3 years, from 1977-79, which would explain why it was so difficult to identify. It came with four different engine configurations: the 5.0 L 302 Windsor, the 5.8 L 351M, the 5.8 L 351 Windsor, or the 6.6 L 400 Cleveland.
So, what do you all think? Is it the same? The only problem is that the door looks a bit longer on the LTD II than in my picture, but that's probably just the angle. I have a hard time imagining another car that had such a similar pinstripe pattern, and handle/keyhole combos too.