It'll be quite unlikely that if you take him to court you'll have any joy. As a landlord myself I've had to go before the courts over unpaid rents totalling an awful lot more than £500. You'll have to prove that even if like me you're entitled to the money that you effectively should have it because whoever precides over the case will take every single aspect into account.
Plus it'll cos more in time, money, stress and hassle that the original amount so IMO you should suck it up and move on.
Would be quite entertaining if you carried on baiting him on here though.