I have run across at least two variations of the 7-segment incandescent displays in
14/16 pin DIPs and they have different case size and pinouts.
First ran across them when I bought four at Radio Shack circa 1972 when I was 12-or-so
years old, to make a clock, but never heard the term 'minitron'.
'Minitron' *may* be a trade name for a particular manufacturer's version,
rather than a 'type' name.
Note that Numitrons are similar 7-segment incandescent displays from RCA, but in a small
vacuum-tube style envelope.