Hi Jan, and others!
Yes, it is pretty easy to revive an old MC meter. Jan, I can't remember the word document, but feel free to share the contents here.
I currently revive old MC meters using solar cells from small solar toys from ebay. Search for solar cockroaches
and you will see what I mean. You just need to insert some extra resistors to calibrate the meter. Another problem is the thickness of these solar cells (the polyester on them), which requires omitting some parts from the original MC meter. We are doing a hack here, so not that important!
By the way, I should give credit where its due, to Thomas Tomosy, and his book titled Leica Camera Repair Handbook
. At page 95 he suggests replacing old selenium meters with modern silicon (i.e. polycrystalline) cells. He says that the voltage in bright light should be around 0.3-0.4 volts.
A technically minded member of this forum whom I have not seen here for a while, has an ingenious and dirt cheap way of reviving the old MC meter. I saved the information as a Word document and can email it to interested parties.
All credit of course to Koray - the inventor......