Glashutte Original Senator Sixties
Hi,
You might want to consider the GO Senator Sixties as well. It's the same size as the UTT Moon 39, for the non date version, while the one with the big date is slightly larger. The UTT39 is a beautiful and comfortable watch, though the date can be a little small for real world use (I have this same watch). Either way, you can't go wrong. The JLC is a great watch and the blue seconds hand is a joy to look at, and that plus the moon phase brings quite a bit of life to the silver dial.
glashutte
Richard N: Thank you so much. GO is definitely something I am looking at. Love the Senator Sixties. Any other GOs you recommend? What about the PanoMaticLunar?
GO
GO has a lot to choose from, and they're all great. The Panomatic Lunar is 42mm though and does wear the size, so it might be new territory for you based on your preference of size. The Panoinverse XL would be another to check out if 42mm sounds about right to you. Just a note that for both these watches, the deployment is less comfortable than the pin buckle for small wrists, but they are wonderful watches by any measure.
The Senator Chronometer and Regulator are two others you might want to look at if you're checking out GO. Both with timeless and classic designs with all the GO DNA housed within.
Rolex daytona
This is a really sexy watch for a woman to wear. Also captures value and also has the advantage that it is a chronohraph. Less than 40mm and is round.
daytona
Posadacastro: That's a great recommendation, and I would get one in SS / Black dial, but I am already planning to get it for my fiance as his wedding gift.... so it may be a bit too much to have two Daytonas! Maybe one day..... 
JLC Memovox, Tribute to Deep Sea Alarm, the MUT Moon 39
These are excellent choices.
The GO Sixties, too, I must say.
A Rolex 116710 also... And so many!
Best,
Nicolas
The Senator Sixties is not only a worthy candidate . . .
. . . as Richard has suggested, but also . . .
. . . lists substantially under your budget. And, while you can't appreciate its unique quality while on your wrist . . .
. . . the entirely sapphire caseback provides the best view of the business end of a watch, anywhere.
Another one to consider would be an Omega Aqua Terra in its smaller case size of 38.5 mm; even the complicated annual calendar version . . .
[yellow gold AT AC]
. . . can be had under budget if cased in steel.
Cordially,
Art