Welcome to genvibe!
If I needed a replacement inner door panel, I'd first ask here (as you did) There are a couple of people parting out wrecked Vibes, don't know if they have the part, but you might ask them. two recently active threads are
viewtopic.php?f=46&t=43041" onclick="window.open(this.href);return false; and
viewtopic.php?f=46&t=41479 There are others too, but I didn't search deep
Next I'd probably try junkyards. If you're in the US,
http://www.car-part.com" onclick="window.open(this.href);return false; can let you search junkyard inventory. not a lot near me, seems to be called "Front door trim panel", $40-$75 for my search, the lower priced ones are pretty far away from me, but some junkyards ship, if you are willing to trust them that the part is in good shape.
You can always try to buy a part from a dealer, but something like that will be really expensive from a dealer.
Do you have some custom thing you plan to do or are you replacing one that got severely damaged somehow?