Originally Posted by
SoreFeet
A regular bike frame will be of higher quality than a mixte...
Not necessarily!
This one is really nice and 58 cm (nearly 23''), it's Reynolds 531 throughout and a mix of a ladies' frame and a mixte what makes it very stiff for a step-through.
[Sorry, not for sale. But you could send me your fiance instead

.]
I've even seen a ladies' Paramount in 60 cm, so YES, they exist, but they are pretty rare.
Good luck finding one, it's possible!