I used arms off an 85 Ford pickup on mine. Had to tweak them just a bit to sit level in park but they fit and work. Bonus is they are J hook style so a modern 18" blade works just fine. I think you can still buy them new from Dorman but I got them from the pick a part yard.
As an aside how did you break a wiper arm? Another Dr Pepper incident?
Something like this?
rockauto ford f150 wiper armMy 72 W200 has the pretty crappy flat wiper arms with the tiny nub to hold them on. One wiper is already getting loose and floppy
I have similar to this
rockauto dodge wiper arm