I have lost my good Motherboards/hdd failures only because of this.
Get some UPS first as it is under 2k only.
You may get online ups later because it costs 10 times more than ups.
Find some 2nd hand pc for temporary need.
2nd hand ups may not have good battery, check this first and then pay.
Battery life is approx 2-3years only.
Get new battery for your old UPS, if possible.
Stabilizer is normally sold for fridge /AC.
But you can use it for computer or any such electronic appliances which is under load capacity.
It is better to use an automatic stabilizer, like this,
if voltage is a problem at your location.