In an embodiment, a pump includes a pump housing formed as a singular body. The pump housing may include a mounting feature adjacent a first end of the pump housing. The mounting feature may be configured for mounting the pump relative to a prime mover. A drive system cavity may be formed in the first end of the pump housing, and sized to receive at least a portion of an axial drive system. A pumpcylinder may extend inwardly into the pump housing from the drive system cavity. A piston guide plate may be configured to be affixed within the drive system cavity. The piston guide plate includes apiston guide associated with the pump cylinder. The piston guide may be configured to at least partially receive a pump piston therethrough for facilitating alignment and axial movement of a pump piston within the pump cylinder.