Sorry, I don't know the bike or the seller, but his selling history looks good.
I do wonder if the bike has just been assembled for sale, though? Mainly cos there's a couple of bolts missing (like the carby flange bolt) and the mag cover is on upside down.
Could well be an absolute gem, but those things and the fact that he's been dealing a lots of Maico spares, makes me wonder if it's worth more than $6k.
PS just noticed the hubs have been painted with the spokes in place too.
Jeez, I'm a picky bastard......