Yes , Imarticus is a good institute for banking courses in Mumbai.
Yes I have heard about Imarticus Learning. In fact just posted something about it. I believe they give good jobs in the top I Banks after the three month course. It is very specific and a good stepping stone to front end jobs as well. A friend of mine goes there now and I believe the faculty is amazing and they are placing people at 4.5 lacs!
Imarticus offers a 3 months investment banking course which would be appropriate for you and at the end of the course they provide you an industry endorsed CIBOP certification and the CISI certified IOC (Investment Operations Certificate). You can go on their wbsite to check out the details about their course.
I am a B.com graduate and plan to apply for jobs to a few companies for an investment banking profile. I want to do an industry specific course for this. Please suggest some good courses/colleges in Mumbai that offer investment banking courses as an MBA may not teach me investment banking in depth.