Roche Burmeister for tools and metals etc etc. 50 Gawler Place Twin
Plaza Metals, (tools, metals etc) 55 Gawler Place P W Beck (for
metals, casting, ready made rings etc), 14 Duncan Court, Ottoway
As someone else added… I also buy a lot online from overseas.
Often cheaper… Otto Frei, RioGrande etc.
Good luck and happy making stuff to your friend.