As above though check out the HBC who do great value on grains.The best way to buy any is in bulk as this will save on postage plus you can mix your grains for a few brews at once reducing your orders over time and there is discount available.
http://www.thehomebrewcompany.co.uk/crushed-grain-crushed-base-malt-c-69_222_223.html
https://www.geterbrewed.com/base-malts/
I get my grains and hops for basic English sort of beers from the Worcester Hop Shop. We get a 5% discount as Forum users.
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