So, of the order of a 100 tons per person. About 10 to 20 moon flights. Not perhaps impossible, but incredibly expensive and you also have to provide water and air. Those could presumably be found on the moon, but the infrastructure to collect them would be another considerable investment. If I was seriously considering this, the first thing I would do, is build a linear accelerator (at high altitude) with a nuclear reactor to power it. That might make it practical to send significant weight of material into space (unlike rockets). However, the potential to use such a system as a weapon would create issues with building it.