Wanted: Rallye Centers 5 on 4 or Good Scrap Yard Locations

Hi. I've gone and managed to lose one of my orginal 35 year old wheel centers off my 72 Dart. Am I gutted or what?
Does anyone know where I can get a set, or maybe just 2? I had chrome but they were weathered a bit, looked cool though.
Or how about the locations of any scrap yards that might have some. I'll be over soon for an extended holiday so will have time to go looking. I'll be in CA,UT,SD,TX,NM & AZ.
Any help would be amazing.
Cheers
Steve