I’ve done more sniffing and have found some.
There’s 2 part numbers from Verbatim.
96689 - a 10 pack
43684- a 5 pack
I can only find the 5 packs in the UK, the cheapest being Â£7.05 for 5, not including delivery.
Buying 50 including delivery it comes out at Â£78.49 which is Â£1.57 per disk. Ouch.