Please help me find an opal

[metro]

I don't even know where to start when it comes to colored stones. This forum is a bit intimidating! I found a lovely setting for a little side project but I now need an opal (my mom's favorite stone). The setting is from MDZ and it's an oval bezel that fits a 9mm x 7mm stone. Where do I start?! Any good vendors that I can buy from online? Suggestions? Tips? Any advice at all would be appreciated. Thank you!

 

[abbit]

There's nice stuff at opalauctions.com

 

[chatoyancy]

There's a sticky with the list of recommended vendors. Also, the advice on the new to colored stones sticky is very good.