There is one country that can give India hundreds of fighters at short notice. That country is USA. USA keeps very large reserves.
But we do not have pilots trained on American fighters.
So it is a lost cause.
I personally think that a lot can be achieved by what India already has - with focusing on maintaining spares and keeping equipment in good condition.
India can still get artillery pieces, tanks, APCs, guns, protecting equipment, many types of ammo, anti tank missiles, stinger type missiles etc. from the West. A lot of army equipment can be easily imported.