For the shocks, the Gabriel part numbers are 82026 (front), 81318 (rear).
100221 was a part number used for at least two different backup light configurations. If yours looks like a 51K park light housing, then it fits the 51K. If it's a larger round light, then it fits the 49K. If it's a teardrop design, then it fits 52-5K.
Front wheel seal = 49640 Victor
For outside mirrors, look on ebay. You car would have used the type that clamp to the door post.
Regarding the molding clips, if you need the type that attach the molding to the doors or front fenders, the KF club sells them. They're $10 and you get enough to do the whole car. If you need the clips that hold the molding to the rear quarter extension, you'll need to hunt around. I think I found a suitable pair at NAPA.
And, I concur about the oil pan. Replace the gasket first...that'll probably solve the problem.