You lucky girl! The neverfull in MM or PM would be great for you, as would the Monty GM. I cannot get it to fit comfortably over my shoulder with a suit, I am heavier than you, but a little taller. I have a mono Musette, but it would be too big on you, since your petite and it's long, not wide. It holds slightly less than a Speedy 30, anyway and is pricey at a thousand bucks, so I would really go either the Neverfull or the Monty. (they have smaller Musettes with a long strap, you didn't say size and they dress up or down and are available in Damier or mono, but I am leaning towards a Monty MM or Neverfull for you.