Do you want solid black? legended? or you can probably find a set of the QFR 'stealth' caps. if you want cheap front printed blacks.
WASD has blanks in several colors, banggood probably has some cheaper ones, but shipping can be hit or miss on time. ( some people a few days, some a few weeks )
God I just ran the typing test, ran only 75wpm. I'm deff better than that, I need to try again sometime.