If the canopy is intact, you might want to try and make a new one. It's really easy, really!
Place the canopy on a post topped with clay, firmly held, and then you can pull a heated piece of Sqaudron clear plastic over the canopy to get a replica that is much thinner. Many people do this all the time because the kit supplied canopy is sooo thick and out of scale.
FSM has had an article about this technique, but I don't know which issue. Good luck!
Matt