Seeing as you are in Melbourne here are my go tos:

Metro Hobbies (physical store in box hill and the cbd)
https://www.metrohobbies.com.au/

Hearns hobbies (physical store near flinders street station)
https://www.hearnshobbies.com/

If you are after paint, some toyworlds stock Tamaiya paints both spray and regular pots, worth asking in the Vic sightings thread for more stores possibly (i think theres also a thread for Victorian stores)