Etronix Pulse F.H.S.S EX3GPro 2.4GHz (Stick) with lots of features is about the cheapest. ( CoreRC Code is same box badged ) ~£75
They do a basic version Pulse EX2G but it has very limited features. ~£45
Try HobbyKing UK Warehouse for
IMAX_B6 AC Charger Discharger_1_6 Cells GENUINE UKWarehouse ~£32 inc delivery
There's a cheaper copy version but they say not as reliable. The IMax is quite popular