What probiotic to take after a juice cleanse???????

I'm starting a seven day juice cleanse in a weeks time, so i am using the following week to prepare myself. I have been told that i should take a probiotic as soon as i finish my cleanse and the brand 'Nordic Naturals' has been recommended to me. However, considering I'm buying all organic produce, mason jars, chlorella and spirulina to add to my juices, psyllium husks and Bentonite to aid in bowl movements and living clay Bentonite to put in the bath to pull out toxins... it's all beginning to cost way to much for me! The Nordic Naturals probiotics are around £20-£30! Does anybody know a UK site for probiotics that are a lot cheaper than this? Would really appreciate some help here, first time juice cleansing!

Thank you.