Best sources for Fire Opal?

[ECUTwinMama]

My sister is in search of one 5.5mm and two 4.5-5mm round fire opals. I've been hunting a bit for her, but without much luck. What are the best sources for some well matched stones?

 

[MJO]

I believe Paraiba International has some nice Mexican fire opal left from the find a few years ago.