This is the second variation of the Optimus 200. In most respects it is identical to the first variation, but the vapouriser was changed to a two piece version. This greatly improved the ease of service. It is quite likely that it was introduced within a year or two of the first variation so presumably in 1932 or 1933.
That is a stunning looking lamp Nils, Do you want me to introduce it to Australia, and the smell of Bundy Rum ?