Two cases sounds good :p I assume you are in Denver you can try this place
http://www.denverbumper.com/ I'm not sure how they will be but its worth a try. You should look under bumpers in your yellow pages (which I just did) or ask a body shop where they outsource their plastic to. Welding tabs is a very easy and quick task so don't let them overcharge you! Hmmm don't cases of beer in the US have 24 bottles? There are only 12 in our cases but they cost almost $20! Let me know if you need any other help.