These seem to be a pretty common find out there on Ebay. You could also try a "wanted" listing as many have pulled them off for larger, or no windshield.
I personally have kept a spare on the shelf, but I now see I am going to try "lace painting" one of them up for my daughter. I have a spare windshield and nose plastic that I am going to do some Pink Lace painting on to help personalize the phazer for her.
I thought it was a good start since I have two of each, they are an easy swap out if one of my buddies wants to ride that sled, but not have it all Pink! My daughter will dig it as it will match her new Castle jacket. She is jacked for the season!
LET IT SNOW!!!