I think you should just treat it like Ivan did; give those that haven't paid a few more days, and then close up shop so the rest of us responsible individuals can get our sets.
One thing I've come to realize is that not everyone apparently has their settings in paypal set to send them an email about invoices, payments, etc. so some people haven't realized yet...I will begin PMing them reminding them to pay very soon...
As much as I'd like to just drop them, of all the orders I have, most are single sets, so If i drop people off for just not paying, we will fall under 250 and not have hit MOQ
so before anyone gets dropped...reminders will go out