To be totally blunt as Aussies are renown for
"you pay shite & you will get shite"
or as grandad use to say
"he who buys cheap pays thrice "
Amazon is good for books,, some times .
everything else is potentially rubbish as Bezos has no quality control over the vendors, most of which are totally annonomous so the perfect site for selling scrap metal pretending to be quality parts as you have just found out
I but mine off Alli-BABA where vendors are identified and must have a real street address and add to that if they get complaints from customers about vendors they get kicked off.
IF I want 10 or more , and I do with 31 series cranks I buy them direct from the manufacturer via MadeInChina
I know this is hard for patriotic flag waving Americans to appreciate that their own man is a crook and that horrid baby eating communist China man is far more honest but unfortunately that is the case.
WFIW the last warehouse I was involved in running used to rent excess pallet space on a weekly basis to people who sold goods via Amazon & Ebay & Buy-Right & other on line sites
They had multiple identities on the same & different sites and in many cases sold the exact same item under several names for several different prices and all of it was scrap
They sent us the picking order + invoice to be included with the package
So you buy the $ 10 cam and it is junk so then you buy the $ 20 one from what you think is a different vendor & get the same junk cam so then you try the $ 30 one, same story
IF they have a lot more to offload then they will give you refund but if most are gone then they will ignore you .