Replacement Nail-In Shelf Peg

I designed this tiny part to slip over some existing shelf nails in a vintage midcentury cabinet I picked up to restore and clean up. The original pegs were plastic donuts that you'd slip over a nail before hammering it in, but the plastic had long since disintegrated. The nails were still solidly stuck in the cabinet and I did not want to risk removing them, so I made this part with a small cutout to slip over the nail. 

I included a comparison photo with the original pegs for reference. 

I printed them with solid infill and 4 perimeters in PLA, and they seem to be plenty strong enough.