Nice list, thanks! I'd really like to see each helmet pictured for the full effect. It seems to me the OTD community has most of them covered.

One question - is there really a Jeb's version, or are there two versions of the Regazzoni helmet? The early one in white with the thin red stripe outlining the visor opening and bottom of the helmet, plus the one with a red top with white Swiss cross and thick red stripes along the side, again on a white base? It was much less usual to significantly change helmet design then (take note today's drivers with your different helmets each F1 weekend!), but Clay was one of the few who did.