apologies for the delay in replying, but i use this one http://www.bayergarden.co.uk/products/242/1
theres a where to buy button bottom left on page

PLEASE ENSURE when spraying that you do it just as goes dark to stop it killing other insects which are about in the day. i'm sure the organic lot here would say don't use this stuff at all as it gets into the plant and anything that attacks the plant for next 8 weeks is dead. i therefore only use the systemic as last resort, ie on my plum tree which was at death's door due to leaf curl aphids and only now is starting to recover.