I second that, dwarf (a.k.a. pea) puffers are the only puffers I know of that would fit in a 10g. I've successfully had three of them in a 10g in the past, housed with a small golden algae eater. Just make sure you give them plenty of caves/fake plants to break up lines of sight and establish territory. They're tiny, but if you ask me dwarves have one of the most interesting personalities.
Good luck!
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p.s. If you give them cup shaped leaves on the fake plants they'll sleep in them. Cutest thing ever. I've never had success with live plants and puffers as mine always seemed to like to nibble on the plants.