>>Aluminium bronzes are most valued for their higher strength
Trust me when I say that the more difficult to machine, the more cost prohibitive. You're best sticking to aluminum and no space age alloys.
It is not cost effective to be trying to create foundries to smelt materials especially alloys if you have no idea what you're doing. You can buy all of this material through material suppliers. There are many local and online based ones you can buy stock of all sizes and materials.
Shapeokos can cut aluminum but with hobby machines its much more about fine tuning tool paths, feeds and speeds, and the specific tooling you use. You have a lot less wiggle room.
By the look of that machine, trust me that thing won't cut dick besides foam and plastics. If you want a 5axis cnc that can cut aluminum at least you'll need a pocket.NC. Only super cheap available 5axis desktop mill I've seen so far.