I don't know details of what you need but I had LMS SaaS application on my portfolio, In that apps also build with ruby on rails with version 3.2.19.
I can not ascertain the time to work on this project because there is no detailed description of the project you want, but I will use Agile Method for every project.
If you want to know about me, you can check my profile on my personal site.
Thanks
Fauzi