[EBB Sightings] bluebirds

Identified for certain a Western Bluebird today in Rossmoor, above the 
BuckeyeTennis Courts (I am using the Sibley guide). The residents have 
put up dozens of nesting boxes for them though I have yet to see one 
occupied. I saw what I THOUGHT was a bluebird last Friday nearby but 
there was no red on its breast. I scoured several  of my bird books and 
could only come up with a Mountain bluebird but that does not seem 
possible here, right? It was a beautiful blue and no, not a jay. The 
closest other bird in that and other guides is an indigo bunting, but 
wrong beak shape and color, wrong territory.

Next purchase: better binoculars. Suggestions for value and quality 
welcome. I do like em a bit smaller if possible.