I don't know about the cheaper ones... I buy all my stopper hardware from EZ=Pots in Seattle... I know they are Chinese made, but the are also the same 401 (don't hold me to number) stainless steel as Ruth Niles.... half the cost... I know she is a sweetheart - everyone says so - but that half the cost is better for me in my pocket.It's not Niles
Honestly its the cheaper ones
Not in need of BS kits right now but will have to check out your sites as well.I buy a pack of 10 for $30 and honestly, they look the same as the site you shared. But, I am pretty sure the seller gets them from StrongInk or PenKitMall
It is Pen Kits MallI just looked up strongink... their stoppers are shrome plated... not had good luck with chrome... only use stainless steel.
Didn't see any stopper fittings at Penkitmall, but kept the site for maybe future use.