It's a Seiko quartz diver 7548-700B from October 1979.
The same model was worn by General Norman Schwarzkopf.
His watch was auctioned under the title "SEIKO Desert Storm" and sold at USD 11,000.
Here is mine. All original but the crystal. There are some tiny nicks and scratches here and there and slightly faded bezel insert, but overall it's in great condition. Nice vintage look already.
I started taking some pics and found a lint at between 52 and 53min.
So, I removed the movement from the case and blew the dust off. It came with a XL rubber strap. As it's a bit large for my wrist, I put a jubilee bracelet for now.
Sorry about some dust on the crystal.
Next to the 7C43-7010.
Another shot. No dust this time lol.
I'm very happy with it.
Thanks for looking!