Special thanks to Mr David Sarles (and the chip guide) for putting up the chip order cards for these, I still keep hoping he'll find more that will help to date some of the others.
None of these were known un-notched until the find (except for the 25p that Ross put on the guide).
The notched one shown wasn't made so only exists notched (I assume).
They are a really nice set of chips although it looked like they had a few problems with the decals falling off as there are 100s that have them missing. Some were still brand new in boxes but almost all were covered in a purple "dye" so needed cleaning with a toothbrush, now that was fun.

Just before I found the "hoard" I splashed out and got the notched ones, oops. Mind you, they are harder to find than the others now.