I think I remember the bike that you're talking about, but it wasn't an 'official' machine...
I'll need to dig out some old catalogues, but I'm sure I've seen a Monster (in the official accessories catalogue) that had a stacked (one above the other) projector headlight arrangement (sort of chrome and yellow bodywork?)
You'll be lucky to ever track one down (given the price of the parts, even then) and the fact the the single/round headlight arrangement is a well loved 'classic' style.
G
