Recently while I was watching YouTube I saw someone talking about https://findbullionprices.com/ which is a tool for finding the best possible bullion prices, and spot silver deals. They track multiple of the most reputable online dealers to find the best prices for silver and gold. They also have catalogs for many coins including some platinum coins as well.
There's a list of the cheapest silver possible, and a list of spot silver deals from different companies.
They also skim some eBay listings and show ones that are available for eBay bucks as well.
Overall, it seems like a great resource for researching which bullion to buy for the best price. I'm sure they can't find every single eBay listing, so between this website and skimming eBay I believe you will find the best deal possible.
I'm not affiliated with this website I just think it's a cool site to check out!
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