My VA, which has been in re-development for two years now (no I am not copying the devs of this magnificent airplane) will most certainly operate the 737-300. Another feature we have is cross platform, meaning that the acars system is compatible with FSX/P3D and my new main sim XP-10.
We opened back in 2012, but I closed in 2014 make some major changes, which are still underway. If you would like to know more, please feel free to message me if you would like some more information, I do not really want to advertise on the forums.
I hope you find what you are looking for in your next VA,
Ryan