Man, I wish I would have been around when you sold your extras. The set on eBay now starts at $110 and I'm sure it will rise. Plus the seller is from japan so you know airmail shipping will be outrageous. Ouch!
You're correct - very expensive, and they rarely go up for sale. The only ship I own is the Mon Remonda, they are resin casts of the original, which I painted. I'd love to own more, but I'll never pay the asking price for the originals. There is a loose Mon Remonda on ebay for over $120! Or you can buy the Courtship of Princess Leia set for $350 - absurd. Another lunatic listing has the set for $700! haha