Advice For Powering 3xCree in 3D Mag

Hi, I hope this is in the right forum? I have a 3D Mag I'm looking to upgrade at minimal cost. After some searching, I think my best route is the 3 x Cree drop-in (with minimal fitting) DX # 9358, rated @ 3.6-9V. What is the best battery configuration to power this module? It seems that the stock 3D alkaline config would just be barely pushing this (?), so I'm assuming there are better options to be used.
*I also considered the MagNum xenon bulb upgrade driven by 4C alkaline (which seem to fit ok with just a bit of tail spring trimming). But I'm assuming the 3 x Cree should be somewhat brighter? Thanks!