no, this was an insider joke for louis who was looking last year for an original pre war mauser model b tangent rear sight for a new mauser hunting rifle project.
when he was asking me if it will be possible to find such a part I was writing him "yes, could be happen, maybe today, maybe in ten years"
to be true I was not very optimistic about this but only some months later such a rear sight come up on egun and louis got it.