Shark Buck, hipCC, hipFlex, der Wichtel buck for driving at full power.
If you are willing to drive at 1.0A or 1.2A, SOB1000 or SOB1227. Makes heat management very easy -- you don't have to worry about it other than making sure you use the usual thin layer of AA epoxy under the P7 slug and add some thermal compound between the heat sink and Mag tube.