https://www.prancingmoose.com/240-od...ml#1981-85_240
All the information you need is here about the gears in the speedo
140 information is here too for cars from 1973 on.
I'm sure you can get what you need from them too,
its in the USA too so not a problem for you as you are in Denver
Also this person knows people who repair classic volvo instruments too
Andy