Where to get the cheapest fidget spinner ? I said chepest, not the best.
From Buying coins;
Or buy the parts and make it yourself, get theses from Gearbest and then buy the 608 bearing separate from Ebay. You will need 3- 4 bearings in total - depending on which model you bought.
If you want the fidget spinner to spin longer - get a different bearing for the center - change it to ceramic.
Ebay - search for 608 bearings
If you want the Fidget to spin longer you have to get a better bearing.