Does Anyone Make Dyes? We Want To Mint Coins Like How The Vikings Did It

Hello sarahnelin and

In York, England, there is a tourist attraction called Jorvik, incorporating an authentic excavated Viking site. Among the activities available is an opportunity to have your own replica Viking coin struck in the traditional manner. You could contact them and ask who makes their dies.
https://www.jorvikvikiNGCentre.co.uk/

@sn, first welcome to CCF. Second, it looks like this might be for a medieval LARPing group. To be clear, are you looking to have custom-designed pieces or just giveaways that are somewhat-realistic replicas? The replica route is going to be faster and cheaper to be sure.

The Society for Creative Anachronism have people that do this kind of thing; I'm sure they can offer advice on what you need to set up your very own mediaeval-style mint.

As for the blanks, it depends on how authentic you want to be. Do you want to use silver, or will pewter imitations be sufficient? Mediaeval minters would usually take thin sheets of silver, cut the sheet into pieces with metal-snips and then trim the pieces down to the correct weight, so they were often only kind-of-round in shape. But for more perfectly round blanks, a jeweller should be able to supply you with some thin silver discs.

Back in the 1960's my father owned a small metal stamping operation
He had an "in" with a local manufacturer that produced hearing protectors for the US Navy
(mouse ears still used today)
As fate would have it one of the parts had a circular hole punched approximately 18mm
Some employees quickly found a use for these useless slugs in something then known as a payphone !
A quick google search found a modern source for similar items
https://metalremnants.com/product/copper-discs/

Believe it or not there still exist folks employed as Black Smiths
I have one nearby who for a twenty dollar bill mended the shaker for my vintage Vermont Castings coal stove
If you find one they may be helpful
Probably a bit amused too .....
Annealed copper disks are easily worked
Whether by a hammer blow or using a small screw press (similar to a vise)
Probably quite a bit cheaper than silver too
Although both can be easily worked after annealing
Ancient dies were of bronze which can be hardened by heating and quenching

Local flea markets can be amazing places to find some simple tools like ball punches very small chisels and files

Start small and work your way up