Get them from eBay:
https://stores.ebay.co.uk/Silver-Coasts/Sewing-Leather-Craft-Tools-/_i.html?_fsub=3104412013&_sid=853213773&_trksid=p4634.c0.m322
these rivets can be used on leather, or fabric, they are nickel free, and non rust.
Post time: Jun-14-2017