One our local MBCA club members here has a nice 250C. The 250C, I believe (vintage 1970 or so) had the same 185-14 tires on 6" rims as our cars came with.
This fellow bought a set of early 1990's AMG rims in the 16x6.5" size, fitted them with 205/55-16 tires. These measured about the same circumference as my 185's. He also checked to see if his speedo was off, and he said it was right on by GPS. I think this might be the size on the 190E.
So, this might be an option for those who want a more modern wheel and tire. This wheel set was a bit earlier that Jim Villers CLK so I don't know if there was a difference.