scoobiedee

On Saturday we drove to plymouth, and the impreza didn't miss a beat.
Walked around the town & shops, when we got back to the car at about 6pm it wouldn't start!
Same as before, the engine turns over but dosen't start.
Luckily i had some tools with me, so i started by taking out the crank sensor.
Didn't start!
Then i took off the coil pack looked at it then put it back on.
Engine then sprang into life. Idled ok, went to drive off got down one level( parked in multi-storey car park.) and the engine just cut out. It wouldn't start so i removed the coil pack again and the engine started. This happened another couple of times.
I was unsure whether to drive home or to call the RAC out as we were along way from home.
I drove around Plymouth and the car seemed to be ok so i drove home.
Got home ok and the car seems to be ok.(At the moment.)
I think that the coil pack is knackered? but could something else be faultly?
Where can i get a new coil pack from other than the main dealer?
Thanks Graham.