COMATELEC RHC 3 have been concieved in the middle 60's and distributed until middle 70's at least (maybe until 80's, I don't really know). Then, most of them have been installed with an HPS lamp. This luminaire have always been extreme rare in France, however, I used to see them in Ile-de-France region (Paris area) when I was young (90's) and most of them were equiped by an HPS lamp.
I have discovered those in Grenoble only in 2008. You have pictured a luminaire which has become extreme rare nowadays.