Get a roll of 20amp mains cable and wire them yourself – speakons are the simplest of all cables to make – no soldering necessary (unless you want to tin the ends), you just insert the cable and screw it down. You can get the plugs for £3.74 inc VAT and 100m reel of arctic grade 20amp cable for £89.12 inc VAT which is PVC insulated and sheathed, very flexible and will take temperatures down to -40C should you ever have a party in the arctic :wink:.

Will do you a good few cables, and will definetly carry any power your amp can put out…