Toothpaste for children

[Chingchok]

Hi there
I am looking for a toothpaste without colouring (especially reds and blues which we've been advised to avoid for our 8 yr old son), and without sodium benzoate, which he is allergic to. We live overseas and haven't been to the UK in a while, so I'm not sure what to look for. Any other tips about ingredients you try and avoid? Thanks in advance!

I use supermarkets own brand toothpaste (morrisons), I've just checked and it doesn't have sodium benzoate and it's white. 49p a tube and has 1450ppm fluoride.

Thank you. I completely spaced on this! I'll check out the full ingredients list on their website.