New Premier Berk finally on the high rail

Perhaps replacing it with a Lionel NKP 765 headlight would work? I'm sure itd be a delicate operation, although there has to be a way to remove the current headlight without damaging the engine. Putting the new one on should be easy enough, as long as you can get the existing light bulb and wire inside of it. The other option that comes to mind is someone with a 3D printer and the skill to use it. If the parts were designed properly they would be easy enough to glue on and make appear to belong on the headlight.

I have one of these models coming, I actually picked this version because MTH advertised it as havimg no Mars light on the MTH site. If you use the zoom in feature, the up close detail photo depicts a 765 with no mars light. Though I wish it had a correct NKP headlight.

Let me know if you find a solution, its a problem Ill also be tackling here in a few days or weeks.

Precision Scale Models has lots of brass headlight castings, including several with wing number boards.  They're in the O-scale steam detail parts catalog on their website.