If you get Reds in the UK you are 90% sure of getting captive bred ones which will be skittish and not much fun to keep.
Also, reds generally loose all their red colouration after 7"/8" and go a silver grey colour.
I dont think there are too many places in the South West to be honest.
Try contacting Carl from www.bananas-about-piranhas.com as he is getting wild reds in soon and can courier them to you. I supply his Piranha so just say Nick sent you.
Nickg
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