Best soil mixture to simulate the lunar surface?

Our team would like to shoot a few scenes of a suited up "astronaut" walking on the lunar surface. We would like to cover an area of 20ft x 20ft with a gray loose soil mimicking the lunar regolith. We only care about the soil looking somewhat convincing and loose/fine enough so that we see the astronaut's footsteps as he walks/hops around.

Is there a soil mixture you'd recommend for visual realism? We can allocate about 2,000-3,000 dollars to this soil and we're located on the Canadian East Coast. Thanks!