So I have been lucky enough to get to GenCon since 2010. However I didn't know about the Crystal Caste Commemorative dice sets. I have the d6 because it was in the swag bag back then, but I really would like to complete my collection and get the Tin and other dice from it. Anyone know where I could find one? Thanks. 

Not terribly helpful, but 2010 was my first year as well, and I just wanted to quickly reminisce about the old swag bag and how it actually had stuff in it.  I remember the beginner deck of Magic cards as well.  Every year I come and see just the coupon books I'm a little sad, even if I understand that there are not twice as many people attending this year as there was in my first year.

The first thing that immediately comes to mind is eBay, but I'm not sure if they'll have something that incredibly specific. You might also try online searches gaming-specific auction or second-hand websites. 

Sorry, that probably wasn't too helpful, but the best I could think of. 

I've tried e-bay but can only find the d6...

Have you tried contacting Crystal Castle directly? Sometimes companies have old stock like that laying around.