This is the only picture I could find of a "vertical aftershock" bike.

https://i.******media.com/CZZbZV4jXv...SiQ.jpg?w=320&

For some reason I can't hotlink to it... sorry... linky no worky.

It's a 20" "full suspension" bike.

From the way the OP talks about it, it seems like the pedal has some of those plastic toe clips on it, and he lost a nut for it.

I'd go to your local coop/bike shop, they're bound to have it.