I have probably seen something close to 100% of the conversion (sealed beam shape/size) headlamps Cibie has produced over the years, and I am quite sure I have never seen one that is both "Euro Code" (ECE) and marked "Motorcycle". The requirement in FMVSS 108 that headlamps conforming to SAE J584 (motorcycle headlamps) and not using a replaceable light source type approved for use in cars and trucks, must have the word "Motorcycle" permanently marked on the lens in letters at least 3mm tall did not take effect until late 1990 -- which was probably done because the HB2 (US version of H4) was nearing approval and NHTSA did not want H4 motorcycle headlamps being confused for HB2 car/truck units. No lamps from anyone were so marked before that date, as far as I can recall. No Cibie conversion lamps were designed or redesigned after that date, as far as I can recall. I think you might be mis-remembering. There were Cibie H4 conversion lamps designed in the 1970s and '80s marked "SAE M" with a year code, signifying compliance with SAE J584 (motorcycle headlamp).
Memory is admittedly hazy. And I probably misused that "Euro Code" descriptor. For a while, some folks tended to use the method to describe the nice pattern we saw from the imported H4 lights, the sharp low beam cutoff, horizontal to center, then 15 degree rise to the right. I don't even recall if the lights were marked ECE. I may still have some in the shed, so I should look.
Now you've made me curious. I think I'll see if I have any of my old headlights (I hate to throw away a cracked light, on the chance I might make it into a spotlight or manage to take it apart at match it to another lens someday), just to see if I can find that "M" marking on any of them.
But I wasn't talking about glass markings. I meant that sellers or importers added stickers saying "motorcycle" or "motorcycle use only." I think it was a legal ploy during a time that the lights were not approved for automobiles in America, but it was legal to import or sell them as motorcycle replacement headlights. Seems to me that somewhere around 1979 or so, Washington, Oregon and Massachusetts approved the H4 lights I'd already been using for some time. I'm not sure the feds ever did. I think the old fed "sealed" standard led to the Cibie Bobi and then eventually evolved to the various bulbs with O-ring seals, 9004, 9005, 9006, 9007, etc.
That's interesting about the permanent marking in 3mm letters requirement. But that's much later than I recall buying lights with the "motorcycle" stickers on the packages. I think it was just another ploy. Heck, I recall buying some 150 watt sealed beam spots with clear convex lens, in boxes with the Simmons brand (same as the rifle scopes and binoculars) from Sportsman's Guide on sale. They had a sticker on the back of each bulb that said "no use for automotive headlamp" but they had exactly the same mounting lugs as a 5-3/4" high beam, exactly the same slip-on connector and even exactly the same three raised "DOT aiming" bumps for a spirit level aimer. I want to say this was in the late 1980's or early 1990's. (No I never used them in high beams, but they were decent spotlights. I think I still have two or three in the shed). Can't imagine stock auto wiring beginning to carry those 150 watt lamps, but I'm sure some fools tried...
My Raybrig R118's arrived. I'll try to get the swapped into the Corolla this weekend. Maybe I will pick up an ordinary new 921, just to compare.