Looking for a footstop? Sure, you could use a spare bushing. But if you want to be serious about it, it's got to be the Riptide Slab.
Height adjustable by way of 3 delrin (fancy plastic) washers.
Throw it either into one of your truck bolts or if you're feeling brave and you know exactly where you need it - drill a new hole in that spot.
This footstop will pivot slightly as you ride and slide which is super comfortable, especially in fast toesides.
Designed by Ambroise Trauet and used in his 70mph+ toeside standup record. But don't buy this hoping you'll do the same - the dude was blowing minds long before he came up with this!