Oh yeah, I misread. DoD not DoD:Source. My apologies. Don't know the answer to that, don't have a 1.3 server, and it doesn't state anywhere. I would suspect it's somewhere in the realm of 250-500. I think 1000 (which only select GSP's are offering) is a pointless performance waste.
Send a message in to UKGame about the HLTV, they'll be able to advise of a cost (if any). I believe you may have to take out a server and then enquire. Quite a lot of people have it on UKGame servers