With strong chinese air defense systems any normal plane will not be able to penetrate 300 Kms into china without being noticed. Perhaps we should go for F35 or F22 .
Usually during wartime nuclear weapons are used as last option when no military could serve the purpose. At this situation both military lose its full potential and its defense system doesn't remain that much effective. For example if India and China engaged in war and both have used their military and feels that nobody can win this war without using nukes then China will rely on missile and they know very well that we are also rely on missiles hence active ABMS can kill our missiles.
Due to both forces have used up most resources to weaken each other hence India can operate such operations with stealth plans having superior EW capabilities. Chinese SAM system won't be that much effective at that time and India can perform such operation.
I personally think that such operations are like "one way" operations that is your fighter plans will be most likely not to return and shot down while returning. So India must buy most advanced fighters with stealth and superior EW capabilities. I vote for F-35, it is stealth and it is supposed to equipped with superior EW suites.