I purchase a pair of standard black painted with chrome base motorized 1978 SAAB 99 side mirrors off of ebay last year with the plans to put them on this car. When I received them, I noticed the paint wasn’t as good as it looked in the auctions so I was prepping them to be painted. When I started removing the paint from the first mirror, I saw a shiny surface beneath. Indeed, it was chromed. I posted on a couple of SAAB forums but no one has ever seen a flag style mirror that was chromed. The other mirror, which apparently came from the same 1978 99, was not chromed. If you know anything about this, please get in touch!
*** UPDATE ***
Apparently all 1978 99 Turbos have black painted chrome mirrors. If you have worn paint on your mirrors, look a little closer, is it shiny underneath or dull gray? If shiny, you might want to try using paint stripper. Do not use bleach or steel wool! Just a sponge or rag with stripper should do it.