pretty awesome that you were able to find and fix the problem
You can buy a fob off ebay and program the car to respond to it, which is what I did. The important thing to be sure of when buying a fob is to get one that's FCC ID GQ43VT141 The FCC ID varies for different makes and models of cars, GQ43VT141 is the one used on (at least 03-08) VIbes and Matrixes, and corollas. If its not that ID, then it won't work with your car. I also have an 03 Toyota Tacoma, its fob is a different FCC ID, tried programming, but the truck one doesn't work with the VIbe and the vibe one doesn't work with the truck
One such fob is https://www.ebay.com/itm/OEM-2003-2004- ... =654425219
(which I not specifically recommending, but is an example) and you can see the FCC ID on the back in one of the pictures for that ebay item.
Fobs that came with a Matrix have an extra red panic button on the back, the ones that came with the VIbe do not. The one I got off ebay had the panic button which I can testify does work on a Vibe to set the lights flashing and horn honking, but the half dozen times I had that happen I did not intend to do it, so I took the red button out to keep me from accidentally setting the thing off. https://www.ebay.com/itm/03-04-05-06-Po ... 2067160322
is another ebay listing (which I am not specifically recommending) that shows one with the panic button, can tell its from a corolla because the third button on the front shows an open trunk, where on the Vibe and Matrix fobs, the third button is labelled HATCH. Still should work. For the hatch (or trunk button) you have to hold the button down for a bit to pop the glass on the hatch, does the same thing as hitting the hatch button in the dash to the left of the steering wheel.
One you have a fob with FCC ID GQ43VT141, you have to program the car to respond to the fob. Keeps anyone with a fob from unlocking your car. The procedure seems like one of those practical jokes where you get people to do a long set of odd steps just to see how long they'll play along, but it works. The procedure is in file http://forums.genvibe.com/files/importe ... remote.jpg
, which is: