Where can I buy extra kyber crystals at Disney?

Excuse me, I'm wondering if you could help me out with a question. I'm a big fan of the Star Wars universe and I've been collecting kyber crystals at Disney. However, I've noticed that I'm running low on my supply and I was wondering if you could tell me where I could purchase some extra kyber crystals at Disney? I've tried looking around but I haven't been able to find a definitive answer. Would you happen to know where I can find them? Thank you in advance for your help.