The originals haven't been made for 20 years but they're nothing special, you could try calling Skybums or the Highwaymen (not sure if they're still going) they might have old stock
Otherwise Decathlon do what looks like an APA clone
https://www.decathlon.co.uk/p/6-mm-conn ... mc=2882077You'd need to note the position of the spar and adjust the C clips to get the height right.
I had a rummage but I couldn't find any good ones, they were pretty poor so I think I binned them all in favour of TW & APAs years ago