Hot Oil Bath Pump Design

I'm designing a heating/circulation system for a constant temperature mineral oil bath. I plan on using a circulation type heater with a pump; however the cost is rather astronomical for a mag-drive pump (~$2K for the one I got quoted).

Here are my system details:

-atmospheric pressure

-total mineral oil bath capacity (Multitherm OG-1): ~14 gallons

-operating temperature: 450F

-desired flow rate: ~10-20 gpm

Originally I was going to go with an independent pump, but the mag-drive pump I got quoted was too expensive. Is there a way I can simply circulate the oil using an axial flow impeller and a motor inside of a U-shaped pipe attachment on the bath? Something like a vertical turbine pump running in reverse. I could even place a screw plug heater on the horizontal part of the U (going back into the bath) to create a combo pump-circulation heater.