Reddit reviews Monster Fastener FBA_SHSPT-005-25 Divided Pin Shelf Rest (25 pieces)

I bought these pins recently as a replacement for that kind of pin and I like them better. They are a bit longer so they are more secure for deeper holes.

But this pin has the same collar.

This doesn't look to be the right size at all but probably provides some clues as to what to search for:

http://www.amazon.com/Divided-Pin-Shelf-Rest-pieces/dp/B003QSEERI/ref=sr_1_3?ie=UTF8&qid=1394121775&sr=8-3&keywords=shelf+pegs

Edit: way more results if you search for divided shelf pin, not sure what your needed dimensions are though.