Thanks for sharing your profile.
How many years should I ideally work?
The average years for most b-schools is 5 years. But it depends on the person and when you feel you are ready. Pay attention to your target schools and make sure you are in line there as well
Which country would be easier for an international student to gain admission and employment in?
If you are seeking to remain in country post grad think you want to look at the countries that have the most international friendly work visa policies
Which course should I go for? MSc Finance or MBA?
The MBA path is more clear with a full blown recruiting process, which should afford more opportunities and a better network
Which universities would be in my league?
If you want to have a chance at securing admission at an IB feeder school you will most likely need to break 700 on the GMAT, from the conversions it seems you are currently beneath that if my converter is working properly
Do I need to take the GMAT? If so, what would be a good score for my profile?
See above