Welcome Paul and thanks for joining.
No doubt you would know, or be able to find out if all three are identical or not.
If they are identical - option:-
Buy one from Audi, then buy 2 matched tensile strength ones from on-line suppliers such Kay’s.
Appreciating that buying from Audi will not be the most economical route, it will be the safest, and factoring in the labour-free DIY replacing, it’s always better to ‘invest’ in the known correct parts.
Kind regards,
Gareth.