Yes, you can use a MJ900 or MJ1200 with the bakpak. Then you need the MJ-VENT Maxiject Turbo Venturi Kit. It makes air inject into the impeller like the rioRVT. So with those 2 items, you would have a RVT type pump for the maxijet.
Keep in mind that the BBX or BubbleTrap2 will not fit over the maxijet pump.