Selochrome Panchromatic - How Old?

I've just been handed a Bessa 6x9 with 11cm/f/4.5 1s-1/150s + B&T ... in the back was a roll of exposed Selochrome Panchromatic as attached.
(The Bessa hasn't been used for decades but looks almost "mint", not a trace of fungus, just a bit of haze and the shutter seems good at all speeds ... it's not mine, unfortunately, I wish it were ... )

According to Photomemorabilia it (the Selochrome) could be as early as 1959 or as late as 1968. On the rear of the backing paper are the digits "1155".

I'll have a go at developing it - I've got all the usual chemicals so I'll try in D23 or D76 (no I haven't got any HC110 or similar) for 12 or 15 mins and hope for the best.

Can anyone date it more exactly? Or give an idea of the ASA?

I have a couple of rolls of Selochrome in the fridge dated 1971, so it might not be as old as you think. Speed wise, the box states ISO 160..

As for development, the times given: ID11 12min, Microphen 10min - This would be in undiluted stock.

Ilford's date codings were on the boxes so you'll not get closer. The film had gone from the shops when I began photography seriously in 1969.

Ian

Paul, Ian many thanks.

I just put some hp5 in the bessa and now I'm half way up a small welsh mountain in fog with it