Kitchen blenders use universal motors (AC motors with brushes) and spin much too quickly with too little torque for a wood lathe. You don't need to be spinning anything at any more than 2K RPM, and most of your work will be around 500RPM.
Baseline I would use a 1/3 to 1/2 HP AC induction motor. Best place to scavenge one would be from an old furnace blower. Ideally though I'd look for a DC brush motor and buy a variable speed control for it; having the variable speed is so much nicer than playing with belts.