Sometimes on BoardGameGeek you can find someone in the forums looking to sell some old products.
You can also sometimes find someone selling them on the Star Ranger forum at
http://www.star-ranger.com/forumNoble Knight games quite often has Starfire for resale at
https://www.nobleknight.com BE WARNED! This company sells a lot of "out of print" games and they charge an exorbitant amount of money.
I have not seen any of the old Starfire products for sale on Amazon, but since they have sellers then I suppose it could happen.
After get all of our products republished we are going to look into making the rules, at least, available as a physical product through a print-on-demand service. So that's something in the plans for the future...