If so, there should be a lot of W114's out there at the local junkyard. I have one in the basement that is marked "38" that is a rear of a 115.

It was not that smart for the overhaul place to don one caliper. The pair MUST be the same.

I've overhauled 2 cars worth of these ATE calipers without ever having a leak problem.

The hard part is cleaning the square o-ring groove very well. Access and visibility is not great when you can't split the caliper, but definitely do-able

The kits were very cheap and the chrome plated piston that seals on the o-ring almost never goes bad.