I have a set of wheels from a 1969 6.3 300sel rightside drive car.
the number is 220/55 tr 390 on the tire. This equates to about a 15.5" wheel, can some one help me out with these wheels. Any info will be greatly appreciated. I have all four wheels one with slightly bent outer ring.

in the late '70s. They featured a different shape to the bead seat, because some of the Europeans were still skeptical about tubeless tires on conventional rims, and in order to prevent the ignorant from trying to mount ordinary tires which weren't moulded for that type of bead seat, they made them in metric diameters which fell in between the time-honored inch sizes. A lot of these were sold on early Fox-bodied Mustangs, starting about 1978, and on BMWs in the early '80s, but by now almost everyone has replaced them with conventional rims, and Michelin has not upgraded the design of the tires they market in these sizes for almost 20 years.

In other words, they're very obsolete and not really desireable.

Did the wheels come with Ben hub caps? If so, very likely they are Benz rims. Also 99 % hance they are 14 inch wheels. Basically worth little to nothing. To tell; clean the insides up, you will find the part number, ET, and size stamped into the steel. Easy way, are the caps real close to 15 inches? If so, they are 14 inch worthless rims.
BUT THEY ALSO migh be alloy wheels. They have some value.

The rarest chance, you have 15 inch wheels, if so, they have value.
Dan in Oregon