First of all no promises, and I'll need to investigate this before committing, so PLEASE do not award the project to me without discussing it with me first, as the moment you do, I have only 36 hours to accept or reject.
I'm UK based, a fluent French speaker and have family in France, (albeit not in Paris itself). I have seen Cotterley in the locale where my daughter lives (Haute-Vienne) suggesting it is probably available on mail order.
As you mentioned Shoptimize, I note one of the shops listed on Shoptimize offering it in Paris is Intermarché and Shoptimize would be my first line of enquiry as they do mail order, with Intermarché second. Please note however that all Intermarché shops are franchised so because one carries the product that doesn't mean the company as a whole lists it. It might be a local buying decision.
However I do strongly recommend you call French Click on 0207 737 1024. They don't list it, but they might know who does. Also it is possible the same tea is packaged under a different name for export and they might know.
I note also that this product is available in Phnom-Penh.
Please note that my £20 bid fee covers investigating the possibility and does not cover the purchase or shipping of the product for which you would be liable on top.
If you are unsuccessful in your searches with the above, then I'm happy to take this further. But as I say we would need to discuss the whole matter first on chat.
Kind regards
Barney