OKAGE: Shadow King

I suggest you go for this after obtaining A Wealthy Slave. There are a few weapons in the game over 100000 Sukel, but they aren't always the absolute best weapons. For example, the best weapon for Ari (Player) is the Sword of Gear which is obtained after giving the Gear man 30 Tiny Gears. So keep this in mind before you go off and immediately spend your Sukel. Here is a list of weapons, their prices and locations that are at or over 100000:

Character/Name/Location/Price
Ari (Player) - Mastermold Sword - Highland Shop - 145000 Sukel
Rosalyn - White Rose Rapier - Highland Shop - 177000 Sukel
Kisling - Ghostosystem II - Highland Shop - 130000 Sukel
Epros - K of Clubs - Rashelo Shop - 150000 Sukel