Try Rick Bailey at Bailey's Boat Service at Nolin 270 242-6293 He can get a new after market pump I would say not a merc pump. He got me one about 4 years a go for my 150 mec can not rember the price off hand but I know it was not $700. give him a call. opens at 7 am cst I think.
John Newton
USA Bassin KY-1-2-3 Director