Note on the 11 speed, You need an 11 speed freehub body for ROAD 11 speed cassettes. Mountain 11 speed cassettes (11-40+) fit on standard 10 speed freehub bodies.
OP, You can try and shop around for used parts, or you can go with Microshift Advent X 10. You would probably be able to get a full drivetrain sans chainring for ~$300 or possibly less.