westend boys
25
5036 or 6036?

As part of my daily work I am fortunate to handle some very nice timepieces.
This is a particularly memorable one!
From a quick search I believe this is either a Rolex ref.5036 or a 6036 and it is known as the Jean Claude Killy model.
Does anyone know how to tell if the watch is a 5036 or a 6036?
It has an engraving for 1952 on the caseback.
Also does anyone know if this reference or similar has appeared at auction recently.
Many thanks for any information you have.