One man striking the die once a minute (four tims that when the bos was around) would easily make 1000 per day. So in batches perhaps 100k per year with a burst of 200k for a new emperor/king. With a population of less than 3 million in the uk (what we will need to get back to next century) and a 10-20 year coin lifespan you don't need many. Probably in a village only one or two people would even have a coin.

They sure managed to get a lot done and with far less people around 2000 years ago

"Have that job finished by Friday teatime or we'll crucify you" does tend to motivate

when in 1723 the local blacksmith + pub landlord having access to some old cannon metal decided to counterfeit some pennies he apparently just used one good penny to make a mould presumeably using clay – the details were not described in the court hearing but many pennies were made so probably the moulds had the imprints of one side + channels for the molten metal to flow with a corresponding mould of the reverse of the coins which would be abutted to the other mould and the molten metal poured into the baked moulds – the small bits of metal from the channels were filed off.
The jury tho the blacksmith acknowledged having made the coins acquitted him as under a new law counterfeiting of brass as well as silver coins was a capital offence (the blacksmith also hadn’t realised but was lucky in that his son had married the daughter of the attorney general!

Many silver coins were quite small and a single master could be used for many copies – the moulds could be reused tho wear would be seen

By way of comparison (and when conditions permit) a visit to the Royal Mint in Wales is recommended.