I found a great supplier for all your Astro hardware/ fasteners needs
Bolts and Industrial Suppliers
www.bolt.com.au
Bunnings fastener range is becoming more limited as time goes on
I ordered M6 and M8 stainless set screws with Allen key head in various lengths which were delivered next day
The prices are ok and good quality fasteners that will last, I can recommend them
They have stores in Sydney, Brisbane and Melbourne plus some regional areas with online supply across Australia
Happy customer !!