There are many ways to gain exposure in the department of your choice. Working as an honorary, a resident or a trainee.
I would suggest the trainee option is the best because you would be given formal training, it would lead to a degree at the end of the 2-3 year program and most importantly, the trainers would be duty bound to impart the standards prescribed.
I would say, please use the junior resident post as a stop gap for a few months at the most. Working with someone, gaining experience and then going for post-graduation is an old concept wherein you would lose valuable time.
If you are still keen on a JR job, it would be difficult in Government hospitals as the jobs need to be funded, advertised and then candidates taken in. There would be good competition for JR jobs as this would be the stepping stones in some good hospitals for the PG intake.
Some reputed hospitals offer Non-PG resident jobs, these are service jobs that are filled in due to the heavy workload but none the less you would get good practical exposure.
The best way is to contact the nearest Government hospital, speak to your professors with whom you have worked in the recent past and the internet
1. There is one job at Lal Bahadur Shastri Hospital (New Delhi), walk in interview on 30th May-1st June for a resident in OBG (http://www.delhi.gov.in/wps/wcm/connect/1915198045ad8b349299fbb6f545cb51/WII+LBSH.pdf?MOD=AJPERES&lmod=-382874882).
2. There are 5 SR/JR jobs at Guru Gobind Singh Hospital, Delhi for this month (http://www.delhi.gov.in/wps/wcm/connect/3253eb80459e2e628373f3a00766aca6/WII+SR+JR+GGSGH.pdf?MOD=AJPERES&lmod=-382874882)
3. Also, check out forums like this (http://www.juniordoctorsforum.com/website/job) which will have information that would be useful to you.
4. Please also look into the charity run but busy maternity units in the cities and towns. These places have less of remuneration but have a wealth of experience to be gained.
Keep an updated CV ready, your MBBS and state medical council registration, experience letter from your last job etc ready. Also, send letters/ email to the reputed medical colleges in your locality. For instance in Bangalore, the reputed OBG units would be at St.Martha's hospital, St.John's Hospital, Bowring Hospital etc.
Based on where you live, I would suggest continuing in the corporate place, it will give you something to fill in the experience gap of your CV. Then while you look into the above, just drop in to meet the CMS or MS of the Government hospital to make a quick inquiry about JR jobs that are just finished or due to be announced.