First off, note that there are now "Enhanced" KNS pushbutton pins - with a cap on the end to make removal *MUCH* easier:
and then note that Primary Arms has the pair (one takedown, one pivot) for standard 0.250" milspec receivers for $30. S/H is about $7 for one or many, so get a few
https://www.primaryarms.com/KNS-Push-Button-TakeDown-Pin-Rear-p/pbtd250bundle.htm
These normally run $15-20/ea for the old ones and not many folks have the Gen2 in yet.

and then note that Primary Arms has the pair (one takedown, one pivot) for standard 0.250" milspec receivers for $30. S/H is about $7 for one or many, so get a few
https://www.primaryarms.com/KNS-Push-Button-TakeDown-Pin-Rear-p/pbtd250bundle.htm
These normally run $15-20/ea for the old ones and not many folks have the Gen2 in yet.