Brake pedal went to the floor, the brake reservoir's rubber bladder seal had been completely sucked into the reservoir itself?

I put my truck into drive and as it began to engage, I pressed the brakes to stop. The brake pedal sank all the way to the floor and would not return to its original position, so I forcefully pulled it back up hoping that it would engage on the second attempt to press it. Still not engaging I began to panic because I couldn't stop and was dangerously close to other people's cars and someone's house. I threw the transmission down to low 1 in order to control my speed and allowed my truck to continue driving. I rode around the block and found a field with space enough to feel safe and entered into it, all the while still tapping my brakes to see if they would respond. I finally decided to force the transmission into park which I had to do by catching a moment where it changed directions from going into reverse and had to be momentarily motionless. I checked my reservoir first and found that the rubber bladder seal had been completely sucked into the reservoir itself and had even been stretched too far out of shape to simply put back on the lid, it also had ripped slightly. Now I'm stuck after hours needing to get to work, which is 1 hour out of town and there is no one to even call and ask for a ride home. But I have access to another reservoir, only this one is simply a twist cap. So why the difference and can it be swapped without doing a whole brake system swap?