I don't think any one is going to compare indian weapons exports to that of China's. India has been very poor in terms of its defence self reliance, it's always goes for the quick fix of importation, that from a nation whose defence expenditure of $46bn and ranked the fifth largest. In fact look at Turkey, who's defence budget is less then half of indias at $18bn has a far better local defence industry and far higher exports.
Why this difference, well it's to do with the way india work or more to the point in defence production doesn't work. Here are a few:
1. Public sector monopoly in defence production and supply (inefficient and encourages laziness) infact where other nations actively encourage the private sector to take up design and development. In india the relatively advanced and effective private sector entities were actively discouraged.
2. Short term planning (or no planning) in fact ALL indian governments are guilty of this, knee jerk reaction to what ever threats they see, resulting in those quick fix imports. If they actually had a long term vision like the Turks, Chinese, Koreans etc they would actually be a net exporter by now, but that's not the way South Asian mind works.
3. Corruption, this goes hand in hand with the above, those who are the decision makers and involved in the purchase of large contracts, have no incentive to encourage local production. Politicians don't matter what side of the political divide are making commissions and black money hand over fist, that's the fact in all importing nations, so why would they change?
Until these and other factors I would rather not bore you with change, the indian defence exports will be limited from their potential.