Thanks, you just made it al the more likely.
Allthough at an effective +10 bonus, it's 200 800gp. Bonus squared times two times thousand gp + cost of masterwork weapon. Considering at lvl 20 you're supposed to have 760000gp, this isn't that unlikely.
Even if the DM is a prick and won't let me shop "à la carte", I take leadership and a cohort Mystic Theurge, who can easily craft this weapon for me.
Note that this is 100% core.