Something to remember is pet shops have big overheads . staff, rent etc. so they charge higher prices because they also want to make a profit. Whereas smaller operations have lower overheads, as they are operated from home and they are usually family run so they have no wages or rent to pay. I buy my rodents/birds from a friend who runs 1 of these, I buy my crickets in bulk because they are a pain to breed ( + too noisy and smelly) but I do breed my own woodies and super worms . If you can find a local rodent breeder , (sorry I don't know any in Melbourne) maybe whoever you bought your snake from will give you a tip ? When you have been in the hobby for a while you get to learn more things