OT Workout Crew: Wood mounted pegs for holding plates

I have a new house and I put my squat rack in the back shed, which has unfinished walls of tongue and groove planks on the outside and just the 2x4 framing exposed on the inside.

Due to the limited room in the shed I would like to hang the plates on the wall, attached to the 2x4s somehow. Rogue makes some short pegs that would work, but they're $43 a piece (which is a topic for another day, because wtf?). Does anyone know of a cheaper alternative? I would prefer shorter pegs. TIA