Northridge has the polymer variety of Swiss stripper clips in stock if anyone is in need. Not sure if they are on the regular website, so I linked their eBay page.
http://www.ebay.com/itm/NEW-ITEM-SE...934337?hash=item5b326b9181:g:CHgAAOSwpDdVXmw3
http://www.ebay.com/itm/NEW-ITEM-SE...934337?hash=item5b326b9181:g:CHgAAOSwpDdVXmw3