Much depends on how much you want - I've always bought mine from CPC - they sell 0.75mm^2 by the metre which is probably too light-weight for a 2.2kW but I've never had any problem with it - plus I live about 10 minutes drive from their trade counter. The usual suspects (Farnell and RS, etc) are likely to sell by the reel which may make things more unaffordable depending on your needs. Google is your friend, CY is not rare.