I wouldn't go 4/rotary axis. You could cut these on a standard 3-axis by using 2 setups. Start with a block of wood, cut everything accessible from the top. Fasten the 'ankle' to a spoil board and machine the bottom (with light cuts, holding it by the ankle is not going to be as secure as would be ideal.) Quicker, but with a bit of extra hand work would be to cut the model in half, machine the halves (still may require 2 setups on at least one of the halves, but there will be a lot more to hold onto.) and then assemble the halves by hand.

I would probably 3d print though. As long as the parts don't need to be heated to the point they'll soften it would be the least work. 3d prints can be quite strong and durable, especially on something as solid as a foot model. Using the right number of wall layers and a fairly dense infill would make a part you could drive a car over without it taking much damage. With the right supports post print cleanup should be just tearing the supports off and doing a little bit of sanding to take off bumps left from the supports. I assume the layer lines shouldn't really matter, but if needed you can smooth abs to gloss with acetone vapor (or body filler, sanding and coating.)
I'm not sure what's around in AU, but it shouldn't be too hard to find a service bureau that could do an FDM print at least as a proof of concept before investing in a printer.