Purchasable, a.
Capable of being bought, purchased, or obtained for a consideration; hence, venal; corrupt. Money being the counterbalance to all things purchasable by it, as much as you take off from the value of money, so much you add to the price of things exchanged. Locke.
Shades of meaning
Fernald has no entry of its own for purchasable; he lists it under venal.
He lists it without comment; the entries above explain its neighbors.