If you can advise the brands you can find in your location, that would help.
Not much point suggesting other brands if you have to import them = expensive.
How much in euro or USD is 5Lac.
(do you mean 1 lac = one hundred thousand 100,000 Indian Rupee?)
With a rough exch rate USD$1 = 1400 Indian Rupee, then 500,000 INR = ~$357USD
Decent 300W panels are approx maybe $50 USD each.
So approx 7x 300W panels.