I would suggest you post about it on the forums and then place it on the player event calendar. I, and the GM Team, watch that calendar to see if we should be there for something. We can not always make it, nor can we say if we will make it or not, but we do watch the calendar and we do try.
Another way you can do something like this is speak about it on the forums and if there seems to be enough interest I sometimes ask the GM Team to run something for that event. Again, we can't make guarantees etc. as we need to work around our own schedules and RL events.