Take the pins out of a door hinge
You know, I just read about this tip on the forum recently, and I went out into the garage last night and took a caliper to things.
I'll be damned if the hinge pin for a standard US interior door hinge isn't the EXACT diameter of a Honda seat pin!
Door hinge pins flair slightly just below the head in order to lock themselves in place, but they still fit right into the hinge on the frame perfectly. The ones I looked at (brass) have slightly thinner heads on them that the standard Honda part but other than that they are exact and look like they were made to go there.
Cut them down to your required length and then either thread the end or drill a cross-hole (or both!) and you're in business. These are very inexpensive, available in various colors and materials, and readily available. Great tip!
mystic_1