You don't seem to understand. Clearly the buyer in this case has tried contacting the seller REPEATEDLY over the last 3 months. I highly doubt the parts were coming from overseas, as the seller was selling parts of his own, not running a business that imports parts for you.
Saying he left the country just after the sale happened is no excuse. If he was willing to take someone else's money, he has an obligation to send the parts in a timely fashion, unless an agreement has been made with the buyer, which obviously is not the case here.
If I sold you $3000 worth of parts, which you paid me for, only for me to head overseas and not send the parts until 5 months later when I decided I'd come back, how would you feel? I'm sure you'd be pretty pissed off that you're $3k out of pocket with nothing to show for it, while I'm overseas.