Nice spotting. Those cards definitely don't look like they are a natural pair and 9 / 10 seems pretty obvious as you state.Something to watch out for, ending tomorrow (Sunday) morning on eBay.
From what I recall, Scanlens 1974 stickers did not come as adjacent numbers. Although the individual stickers in question are in very nice condition, the description "... Mint Condition..." is very false. At some stage one or both stickers have been removed from their original mismatched pairs and re-arranged in order. It's hard to tell for the 7-8 pair but very easy to tell for the 9-10 pair where the stickers have aged slightly different and the lower edge of the 9-10 stickers are mis-aligned. Basically, neither sticker-pair came out of a pack like this. They were probably arranged by the original owner this way so as not to trigger their OCD.
The seller may or may not know exactly what they are selling but the buyer will probably be unhappy to learn they are not getting an original sticker "card".
Fyi, I recall a full set of 6 pairs like this (ie, 1-2, 3-4, 5-6, etc) split up on eBay in the last year or 2.
I'm pretty sure though that there was the odd ones released in ascending order number. I have a note in my PC that there is a possibility of 22 different variances of a St George sticker (STG first then 11 different clubs last and St George last with 11 different clubs first). A quick hunt shows an example on Dans NRL below:
https://www.dansnrlcollectables.com...Rugby-League-Sticker,-Manly-v-Parramatta.html
Cheers
Ross