First of all, let me state that I am a rank amateur at metal working
but I have had a thought re. your stuck drill bit that I haven’t seen
expressed on the forum.
Pewter is an alloy that melts at a low temperature (compared to silver
What about using a large soldering iron or gun (probably 100 watt
rating) and touch the end to the exposed end of the broken drill bit.
This will in short order conduct heat down the bit into the portion
that is “captured” within the pewter, possibly softening the pewter
enough to twist the bit out with needlenose pliers.
See there, I told you I was an amateur at metal work. Now you must
surely “believe” I was truthful.
I hope you find a method that is sucessful.