Hoffman 1895 batiks would probably have the most color saturation and choices in deep vibrant blues and reds. But they don't have any design to them just that watercolor look. Have you tried looking at Hancocks of Paducah? They have the largest selection of 1895 batiks at $8 per yard. They are having a close out sale right now on a lot of other batiks priced from $5 to $7 per yard
http://www.hancocks-paducah.com/Item...c-Sale--m-3761
I saw some blues but not many reds.
You can also try Thousands of bolts where you can search by color and fabric style.
Batiks Etc has tons of choices:
http://www.batiks.com/cgi-bin/Store/store.cgi