Wait, let's take a second here to calm down. Panic is never a good state of mind in which to make a financial decision.
Take some deep breaths and evaluate the situation.
There's something I don't understand... WHY can he only sell you one?
Logic tells me that if he's willing to part with ANY of them, he'd also be willing to part with ALL of them.
So why would he be limiting your choice to just one? Unless he's deliberately trying to whip you into a frenzy.
Tell him you'll take them all, see how he reacts.
Or is it that you can't afford all of them, so you've been given a 'first pick' chance?
I say, cut out the middle man. Stop relying on what your friend says his brother says, and you speak directly to the brother about this transaction. Maybe something's getting lost in translation.
Anyway, if you're having this much trouble deciding what you want, my gut tells me you're not passionate enough about it. Don't ask us what WE would buy. Ask yourself what character makes you smile the quickest, gives you the warmest fuzziest feeling inside.
If there's still no clear-cut winner in your heart or in your mind, either you want them all equally or you don't really want them at all.
Be prepared to walk away from it. Just say, "I'm not going to make a purchase at this time," and revel in the power it gives you as the consumer.
These things were mass-produced. This is NOT your only chance to ever find them.
Patience!
Alex