The quick answer would be - this one:
https://omegaforums.net/threads/seamaster-st-2828-cal-470.37765/
I bought a similar sized one for my girlfriend, and it's an extremely pretty watch. The one I bought was gold capped.
View attachment 219305
They come up for sale pretty often, and are very reasonably priced when looking at condition compared to "regular" sized Seamasters of the period, and wear well due to the thick lugs. My girlfriend wore her the day before yesterday at a fine restaurant, and I could compare it to the ladies' Rolex which the lady next to her wore - absolutely no contest.
EDIT: by the way, my girlfriend has slim wrists as well, and I think that this piece suits her better than a mens' Seamaster. She's quite taken with it as well, even though owning it has made her look at my Constellation now...
Here's an older photo with two regular Seamasters, both now gone...
View attachment 219306
Click to expand...