There are now (end of February 2017) 777 blueprints ingame.
There are four sources where they come from:
450 basic blueprints. In each of the 25 categories are 18 BPs.
217 chest blueprints. Wood 11, Leather 19, Iron 26, Gold 36, Magic 58, Dwarvish 23, Primal 44. Every category has 8 or 9 BPs.
101 package blueprints. 36 permanent (6 packs à 6 BPs each), 65 seasonal (20 packs à 3 BPs each, Valentine with 4 BPs and 1 BP from OSD)
9 raid blueprints.