Please, please, please do not use curtain rod rings (sorry Tanya!). They are not designed to weight bear and are not safe for baby carriers, especially as the rings are a significant pressure point when tightening a carrier. There have been incidences where haberdashery rings have broken during use and they can cause serious injury. If you are going to use rings that are not specific for babywearingthen you can safely use mariners rings, but they are much heavier and aren't very comfortable. The WeeWuns do have proper sling rings, they source from slingrings in the states - you can buy direct from slingrings too in small quantities at a much cheaper price.