Deb,
I've never heard of a coerulean form of
Cattleya amethystoglossa, so anything a bit larger than a seedling may prove to be in the hundreds range.
However, seedlings of
C. amethystoglossa are relatively cheap, but they need much time to mature to first blooming. Blooming sized plants range from $30 to $150, and many that I've seen (especially offered on eBay) are not of good flower or plant quality. The plants can grow quite tall, over 2ft. in some cases...
Who's offering the corulean
C. amethystoglossa, out of curiosity?
-Pat