i have a Eco Tester1 , was like 60$ish from a shop a whiles back. it just tests Ph but ive had it for almost half a year now , and it still works perfect and still hasnt needed a calibration, i test it in a 7.0 solution every now and then and its dead on. So i fer sure recommend that brand.
check out Hanna instruments I think they have a decent Ph/tds stick for about 50-60 bucks. I found it surfing Amazon try that. I got an HI9813 which is a great meter I love it but it might be just slightly out of your price range.