1964 Seamaster 166.002 - advice please?

Well to start with I would never entertain a seller who first needs payment before he'll provide me with additional pictures! Just outrageous and reason enough to walk IMO

Areas of concern on these plated cases are the edges of the lugs. You can see on the photo the lugs have dark areas, these look to me like plate wear....certainly something that needs checking. A worn plated case is tatty and can never really be proudly worn. I'm not sure the crown is correct for the ref. the style looks a little early for the baton markers and stick hands.

As for the price.....if it was mint, then just maybe, but I see this more in the €450 kind of area, lower if the lugs have plate wear through

Welcome @fatclive

as @cristos71 has pointed out, the seller is a prick and the watch is beat. I wouldn’t even give it a second thought.
These watches are abundant- nothing rare about them. Lots of dial variants, some are rarer than others, but cross hair dials are pretty common. Gold plated have to be flawless to be worth buying and this one is far from it. Sold gold, gold capped and stainless are your beat options.
For $900 you can find a near flawless stainless or gold capped in the sales section here, they pop up in that price range regularly- you just need to be patient and fast with the PM.

Birthyear is hard to verify unless the watch comes with an extract of archives- which costs money, and for a sub $2k watch, a seller isn’t likely to provide one (I wouldn’t). Serial numbers can get you close, but not specific to the exact date as movements were often made in large batches and could have sat in stock for years. Try not to get hung up on birthyear specifically and find the right ballpark era, and focus on condition above all.
Glad you checked here before giving money to this idiot.

I’ve bought on Chrono24 and sellers have always provided more information when asked, including documents confirming the servicing of the watch etc (assuming that it refers to the watch I’m buying) so I echo what’s already been said about the seller and the price. Pass.
I also agree that the crown is older than the watch, and that would always put me off

Wow. That selling practice really is something else.

You’re interested in the car? Happy to show you the engine bay - after you pay in full.

Dodgy to the max.