I don't have any pics of ring dies, but here's a stickpin die from the Danish resistance of my local town.
I don't have one myself (althought looking for one), only one i have ever seen is the one pictured, which is in a local museum depo i used to volunteer at. Death head stickpin dated 6 may 1945, and with text "Ribes Gr�nsevagt" (Ribes border control). Given to resistance fighters from Ribe who were stationed at the Danish/German border.
Who commissioned them and why they used a skull in the design is unknown, made by Ribegold smith Bottelet, Mellemdammen. The museum depo has both the stickpin and the original die to the skull.

Would love a copy of it as filler, but i doubt i'll ever find one frown