Bad Brake Booster?

[Mark Brye]

Hi Guys, need some advise. I have BDR354 which I have about 6000 miles on. I went to pull out of the garage today and had no brakes. The pedal is hard as a rock. There are brakes but I would be better off dragging me feet to stop the car. My first thought was either my electric vacuum pump stopped working or I lost a line between vacuum pump and booster. I pulled into the garage and turned off the engine and turned off the fuel pump so I could here if the vacuum pump was working.
I pumped the brakes and my vacuum pump turned on, created vacuum and then shut off when it reached full vacuum. It held the vacuum for half an hour without turning back on. At this point I tapped the brakes, putting the pedal in mayby 1/4 of an inch and you could hear all the vacuum whoosh and bleed off instantly and then the pump would turn back on. In the past I could get 4 good pumps on the brakes before pump would turn on. Now, if I just touch the brakes I loose all my vacuum. Does this sound like the brake booster has an inernal leak?
Any one know what the p/n is for this build number 354? Thanks!