You might want to look into making your own greek yogurt. It is an extremely simple process. All you need to start it is milk + a little bit of greek yogurt. Then you can use the yogurt you make to make future batches essentially forever. Much cheaper and easier.
Can you find skyr or something similar and is it affordable? If not you could go for protein supplements, maybe you can make your own snacks, like nutbars, other kinds of bars and add protein powder. Hell you could put a scoop of protein powder in your yogurts if you want.
If you find hitting your protein hard and expensive one of the cheapest best ways is increase egg intake if possible, or shakes, a regular 3dl milk + 3scoops protein ≈ 40g protein, 300 calories. Split it in two or three if you want several snacks, you can freeze them as popsicles.
Low fat/reduced fat yoghurt is the worst of the lot. They market the notion of ‘low fat’ but there’s so much added sugar instead. You actually want the fat in the yoghurt. Yoghurt is pretty easy to make if you have an instantpot or similar pressure cooker. There’s a few videos on YouTube.
I wouldn’t rely too much on yoghurt for the protein content. There’s much better sources.
I love yogurt and would love to have it often, but like you, I live in a country where greek yogurt is so outrageously expensive that even if I can afford it, it’s so overpriced that I can’t be okay with spending that much in just yogurt. I’ve looked everywhere for other good options and there aren’t any. Just stay away from yogurt. Those low fat/no fat are smothered with added sugar. Not worth it.