I can make these M8 seatpost binder bolts by welding a piece of spoke to it.

I'm looking for a bulk source for these where I can buy 50-100 per order.

I need only the bolt. I do not need the washer. I do not need the acorn nut.

There appears loads of them on auction sites, but I am not interested in buying retail as my target price for this bolt is under $1.

Ali appears to have only the upgraded binder bolt, which requires a tool on both sides, the same as using a regular M8 bolt and nut.

This binder bolt is commonly found on all big box store bikes from all eras, past to present.

The reason why I must include this binder bolt with the bikes that need it is because it eliminates calls I get from clients that only own one monkey wrench and they keep asking me how to stop the bolt from turning. Many resort to using pliers and screwdrivers and seriously scratch up their frame.