we got the club ones from MrFlag http://www.mrflag.com/
250cm x 80cm Feather Flag. Came as a complete kit with pole, carry bag and ground screw base. Take a couple of weeks turnaround though inc printing
What do you want the flag for. Is it to show the club. If so you can borrow the club flags from Chris in Chesterfield. You must return them when finished.