If it's got 6 lugs then it's a DPDT (2x3), a 3PDT would have 9 lugs. You *can* get a DPDT footswitch from Maplin, but they're cheaper (and better quality) from places like pedal parts:
[url="http://shop.pedalparts.co.uk/Alpha_DPDT_Footswitch_-_Latching/p847124_14395207.aspx"]http://shop.pedalpar...4_14395207.aspx[/url]
or doctortweek, (his site's been down for a while though).
Ideally I'd go for the 'Alpha' brand, or what are known as Taiwan Blue, as they're much better quality than the 99p eBay specials.
Whichever one you go for make sure it's a latching switch, otherwise you'll have to keep your foot on it all the time!