The Fabulous Museum of London online archive,
https://collections.museumoflondon.org.uk/online/group/19998.html 

A few select pieces in the British Museum's collection, 3d zoomable models,

https://sketchfab.com/britishmuseum/collections/digital-pilgrim

The Religious and Profane Medieval Badges Foundation's excellent site

http://www.medievalbadges.org/

The UK Portable antiquities scheme database. 

Hundreds of pieces, growing every week.

http://finds.org.uk/database

The UK Detector finds Database,

http://www.ukdfd.co.uk/

Kunera, the Dutch Archeological records database

http://www.kunera.nl/Default.aspx

there are a few interesting moulds in the Petrie collection. they are from Egypt, and probably for Gold & Copper items, but the principles are the same.

http://petriecat.museums.ucl.ac.uk/

An interesting bunch of Andalusian finds collated by,

Gaspariño, Sebastian. "Amuletos de al-Andalus". 2010-2012 

http:www.amuletosdealandalus.com

And some Moulds from Mont Saint Michel

http://www.inrap.fr/preventive-archaeology/Events/Virtual-exhibitions/Virtual-exhibitions/Making-Pilgrim-Badges-at-Mont-Saint-Michel/Pilgrim-badge-moulds/p-1482-lg1-Iconography.htm

content rich , but searching is awkward,
https://art.rmngp.fr/en