You can try puffing your own: take amaranth seeds, put about a tbsp in a hot pan and shake it. Kinda like making popcorn the old-fashioned way. I tried it once but had a lot of un-popped kernels.
Or you can try other puffs like quinoa puffs, millet puffs, I'm sure they'd taste just as good with the peanut butter and honey. They might also form more of a bar.