well that charger puts out 5 amp max so if you only plan to use just that charger then you could get a 8 amp supply like this one,
http://www.ebay.co.uk/itm/Fusion-12v...item35b4d615e8
or 1 of these 10 amp ones then you could connect 2 chargers,
great seller and charger
http://www.ebay.co.uk/itm/Nosram-10A...item4cfa2de4b2
or you could get one of these 20 amp ones then you will have enough power for another say 2 chargers, 1 cooling stand etc,
http://www.ebay.co.uk/itm/Pro-Peak-p...9#ht_500wt_969
i use the latter and have 2 chargers, a cooling stand and a light and a tyre truer connected at once