You can claim recycled content as a regional material, and you don't have to trace it back to its original extraction location. According to the LEED Reference Guide, the extraction point for recycled materials is the location of the raw material prior to the manufacturing of the final building product. That might be the recycling facility, scrapyard, depository, stockpile, or another location where the material was collected and packaged for market purchase before manufacturing. It is not necessary to track the raw material back to its original point of extraction.