That's terrible that sets were shipped without it and it couldn't be replaced!
I bought it when we learned the set (9001) was going to be discontinued, I guess I bought one of the later/last batches produced.
(when unboxing a set I´m always very carefull to get every small part out of the carton and the plastic bags, so I´m 100% sure the visor did not come with the set.)
When contacting DS immediately afterwards, the visor was also not available anymore as a spare part.
So I assume they ran out of the visors during the last production run, didn´t find it necessary to produce some more and sold some of the last sets without it.
Would also explain why it wasn´t available anymore as a spare part, when the set was just on the brink of discontinuation.
Or did they just tell me it wasn´t available anymore, as the visor is part of the helmet and the helmet then belonged to a "licensed" klicky??