Thanks Mate.
TBH I was very suprised there wasnt more pieces missing. I have a darth vader one as well but no pieces in the box
I think they fell out over the years and just got left behind as most the time they where stored in out Loft and moving from house to house has meant they have spilled out a few times.
I might be able to find 1 or possible 2 more pieces to try and make it complete but its doubtful. It cost me 5 pence when I was about 8 years old so $10 is a significant increase
Not sure if I should try and sell it as it was mine from my youth but I probably wont ever get it out again.