Engines can be acquired by
Russia
France
UK
Sweden
Japan
If needed you just need the dollars
But Yasser is correct Tejas will need to be curtailed to just 100 planes and order long term two hundred engines now for avoidance of embargo in future ...
Any future Indian built fighters powers by the Safran engine next generation which France and india signed to recently
Remember china was completely reliant on Russian engines until.five years ago
Fighter jet engines aren't exactly one size fits all thing.
Russia =
RD-33/RD-93 2 would require redesign of Tejas air-frame or the engine.
France =
SNECMA M53 (Mirage-2000/2000-5) would also require redesign of Tejas air-frame. There is no time for that.
SNECMA M88 (Rafale) would be the same case.
UK =
EJ200 (Eurofighter) is closer to GE 404 and 414 but would still require rework of either the engine or the air-frame. Besides, the sale would require approval not just from UK but also Germany, Italy, and Spain.
Sweden =
Volvo RM12 (Gripen) is a variant of GE F404. This might work but would need approval from the US as it incorporates US-origin items.
Japan = There doesn't seem to be any fighter jet engine available for exports.
IHI XF5 is closer to F404 and perhaps could be modified but it is a technology demonstrator.
In short, even if any of these are available either they would need modifications or Tejas air-frame would need to be redesigned. There isn't anytime for that. F404 and F414 have been adapted for Tejas and deviating from them simply means Tejas will not be available anytime soon, or perhaps never.
India will have to go with France. But that collaboration would not yield anything in near term, whereas Tejas requires engine now. Also, with France gearing itself up for next-gen fighter programme I wounder if Safran, which is the prime contractor for developing engine for FCAS, would be able to commit or timely develop an AMCA-specific engine. Correct me if I am wrong, but I don't think Safran's facilities based in India are as yet equipped with developing or producing complete engines.