These were holding parts of my interior to the boat pretty solidly, trying to find new ones when the interior goes back in but not having much luck. Have tried Google, Amazon, McMaster Carr and a few automotive body shops with no luck. Need them in 1/2” and 3/8” diameters.

Amazon , search double sided push clips

Too small

Have you tried to reach out to the Amazon store that is offering the clips and see if they have access to the larger diameter? At least its a lead to search as there is very little in online offering for those pieces much less a large diameter

Take a look thru the catalog and criss fingers lol
https://www.auveco.com/