You can make one pretty cheap and efficiently by capping a length of tubing, taping it for hydraulic fittings, and welding or machining heat sinks on or through it. Keep the ratio of tubing ID relative to hose ID to not drastically change flow rates or create a bottleneck. Pressure test it with air and soapy water.
Might not be as good as Matt O's Howe set up, but near free and better than nothing.