800km requires targeting much more precise than just satellite and requires positioning and updates that are susceptible to jamming.
Keep this in mind, you already have coverage via other "systems" well into their ports where they will likely load any amphibious forces and further out where they could try flanking maneuvers.
Having 1000km range is one thing, making sure you can guide it to a spot where its own sensors sans positioning systems can get a reliable lock and then also have enough of a salvo to get through defenses is what matters.
What's this 1970s?
Missiles will be 1000 km range
Not targeting at 1000 km range from shore
You fire missiles
Guide them via MPA, j10c aew drone and satellite that are already about 300 km near Indian navy assets in ocean
They are outside Sam envelope
Targeting gets hard but you need to do hard to keep enemy away in a2 ad
Also 500 km brahmos already available for few years
800 km brahmos tested couple years ago from different ships
You can't outdo IN in magazine depth
They have 8 to 16 brahmos 500 to 800 km per vessel
You will need years to build destroyers or still years to build many Fac or type 54B size frogates to get 8 to 16 smash per vessel
While it is simple to just deploy longer range smash from shore
Guide via areal assets
And don't say j10 c don't have range
Refuel in our airspace over sea
Already 300 km from shore
Then with it's 750 km radiuses it can guide it to in destroyers
Also nobody in forces downplay enemy like Indian can't target at longers ranges and we should sit back and relax
If that were the case
PAF should also have relaxed since Indian Rafael can't target meteor to maximum range
But they did outgun them
AWACS guiding at long ranges being outside of Indian AD coverage for both fighters and AWACS
Simply put
Indian navy can outnumber and outrange Pakistani ships with number of ships number of missiles per ships and range of missiles
But they can't touch long range targeting aircraft guiding 1000km shore based missiles due to their 150 max barak range and that too consider s400 had double range against j10c but those are theoretically ranges
Also, IN cannot defend against ballistic missile
Barak has no such capabilities
Not did Indian radar of navy