I stumbled on a black Pentax SL the other day with a 50mm super tak attached. On closer inspection it had a serial number that instantly made me think eight element. Looking at the rear element confirmed this so I grabbed it (bargain).
Anyway here is the lens.
On checking the serial database I could not find an eight element serial that came even close. When I compared this lens with my otehr eight element there was font differences in the numbering, with numbering being more consistent witf the Auto Takumar series.
Anyways I humbly call on all those with an eight element to compare their serial with this to see where it stands in the 'age department'. I suspect that this could be one of hte earliest ever produced, but happy to stand corrected.