Going from 5 to 10-model Repentia squad? (UK)

I have the 5-model repentia squad from the old combat patrol (4 repentia and 1 sister superior) and want to get to the 10-model size instead for better use in game (and in case 11th edition removes the 5 squad size), however I'm struggling to find how to get another 5 models without just paying same or more money than it would cost to just buy a new 10-model box.

Anybody done this or have you all just got a squad of 5 only or a spare 5 on top of a regular 10-model squad?

Ebay seems to just be singles or bits, which when buying 5 ends up more costly than just the full box. Most 3d Prints are "sexy" which isn't what I want for my army and the ones I've found that I like the look of have £15+ delivery to UK, causing it all to cost more than a new box. I don't have a 3d printer but if anyone knows any good models and sellers that deliver to UK cheaper please recommend.

Am I just stuck with a spare 5 or anyone else found a cost effective solution somewhere?