There actually is a 9-speed freewheel made by Sunrace. There may be axle length and/or spacing issues to look into, perhaps someone knows more about those concerns.
http://www.niagaracycle.com/product_...ucts_id=502502
Universal has 'em in their Minnesota warehouse. Might be quicker to Chicago than Niagara.
http://www.universalcycles.com/shopp...&category=1665