i would trade it back for a primary without the hole! your parts dude messed up :P

 

Mindy some of your larger auto parts stores might have what you are looking for. If not try google, I just saw a bunch of links to businesses on there with a huge variety of vinyl and plastic plugs. Good luck and welcome.

 

If they said it was compatible they should have at least give you a plug. If I was you I would try and take it back and get the right one. You can buy rubber rimmed hole plugs made for different thicknesses and diameters