Splash guard push pins

I bought replacements through Amazon. They're not identical to the originals, and not particularly better, but not worse, and much less expensive. A problem I found with many of the Amazon listings is that they didn't specify the critical dimension, i.e., the nominal hole diameter they fit---although they may show useless information like the dimensions of the package.

Yes, more people would likely see your post in the 3rd-generation section

 

I bought these off Amazon and replaced nearly all of them on my 2012 Prius v.

Surprisingly, they are better than the original Toyota ones.

Ziruiautopart 100 Pieces Pin in 7mm Hole Compatible for Toyota 9046710183 Plastic Rivets Car Clips Fastener Push Clips Retainer for Cars for Scion Lexus

 

I got an ebay kit, but none are an exact fit replacement for either the the engine under panel or the fender liner pins. I use two different pins from the kit on the engine under cover panel, depending on the dimensions of diameter and depth of the holes the pins fit into.
Some ebay pin sets give all the relevant dimensions of the pins. To know the dimensions one or all the pins need to be removed and measured in millimeters ....
An easy hack that works for me is to put a dab of Dawn or Dishwashing liquid ( none diluted ) onto the pin and work the center of the pin untill it slides without any resistance, than reassemble as usual.
It only works well for about 6 months, leave the pins untouched for longer than that and breakage is just as likely as un lubed pins.

 

It was 20 identical ones of the size for 7-mm holes. That's the most numerous size on my car, but it also has a few similar fasteners in 9 mm holes. The brand is "Approved for Automotive."
When I bought the car (as "certified" used from a Toyota dealer), the 9-mm pushpin was missing from the oil-change flap, so the flap was drooping. They replaced it without charge when I complained.

 

If you want assured compatibility, just get the unimproved Toyota fasteners? You can find the parts numbers if your root around on parts.Toyota.com, and then maybe get them from a dealership parts department: let them come up with the parts no's, and verify against your research.