I wouldn't worry, to be honest.
Don't get stressed about it.
If you paid through PayPal, you're pretty much completely covered regardless of what happens.

The guy might be a complete arse. He might be disorganised, negligent, ignorant, and not give a f"ck about his buyers. But there is no evidence yet that he's a fraudster or a thief. By all accounts he sends out everything and the majority of it arrives and his buyers on both his eBay accounts are happy.

Seriously, don't get stressed about this. They'll arrive. They may be late. He may be over worked and disorganised 'cos he's selling so much, but he seems to be an honest guy. Some people are just crap sellers, and selling volume is difficult for anyone.

Sorry I'm not in the States, so I can't help you there, but I thought I could give a more detached/objective view of things as they appear to be.

While it might not sound like the nicest thing to do, I would move directly to "claim" after 48 hours.  Don't waste time as it sounds like he's probably not going to be shipping anything soon.  The sooner you get it started, the sooner it will be finished and you can move on to another sale.

I got an indignant email from the seller stating that he replied three times to my emails... I replied that I find very interesting that this one 'fourth' email arrived with no problems while three former ones went 'lost' and that I got an answer one day after opening a dispute via PayPal    He alluded to some attempt to fleece him unfairly too...

Anyway, the parcel is struck in Italian customs (please God...   ) and so everything is officially solved. This year collector Christmas will be in August. Yay!