My local (Duvall, Wa) True Value has a decent hardware aisle with lots of nuts, bolts and all sort of other fasteners. Metric and USA. Chrome, stainless, etc.
I went in looking for a 3/16" key for a sprocket and 2 set screws. They had 'em! 0.40US$ each.
But more exciting - they had #41 regular links (.69$) AND #41 master links $1.09 each AND they had #41 1/2 links - I was amazed. $1.40 each!! Good prices too. (they had other chain sizes as well, but no 415)
The hardware is sold in stacked metal cases, slide them out, top hinges up and is marked with the contents and price of each tray. Better than the slide out donut tray!!
(Helm's bakery truck memories)