Sorry if this has already been mentioned before, but I haven't seen it elsewhere, but the Orison Bliaud also gives additional MDB to barspells as well.
The first stonega III was naked, no barspell, second solaced barspell and third bliaud barspell. No gear other than that was changed, only had cruor buffs as well.
I'm not sure how sound my math is because there are two unknown variables, being dint and mab of the worm. Just for the sake of it, however, I got dINT 11 by reverse calculating. In any case, it shouldn't matter much if the dINT or the MAB/MDB part is wrong since it should work out to be the same.
(434 + 11)/1.18 = 337.118~ -> 337
(434 + 11)/1.33 = 334.586~-> 334 (barspell merits and solace bonus)
(434 + 11)/ x = 311; x = 1.43 so if this is even correct, +2 body gives 10 mdb.
Again sorry if this has already been mentioned >_>, if it has, I need to lurk better.