Surprised no one local has given you a response. There is a car park at Pistoia station, leave a bit of time and I think you should find a space, but I have never tried to use it at 9am.....so I am guessing. If you are lucky and grab one easily have a coffee at the station. Don't forget Pistoia is a commuter area for Florence, the area around the station is therefore popular with locals, so it could be rammed. My guess on cost is a real stab in the dark based on Lucca, as much as €1.50 an hour, but likely to be less. My advice is leave plenty of time and don't be tempted to leave it somewhere you are uncertain on costs/permission, enforcement of parking is pretty strict in most towns.