Hey Chris R.,
The pedals we use on Halfbike are by VP Components, but as Chris S. concluded the crank arms do indeed have a standard thread size, so any pedals you like would work on your Halfbike. If you're curious and in search of an alternative, you might want to check out some of the options shared here >>
halfbikes.com/pimp-my-halfbike
Hope they help a bit :)