I use Milwaukee meters. Here are some Amazon links for you to use as reference.
I have one of these
https://www.amazon.com/Milwaukee-MW802-Digital-TDS-Meter/dp/B007Z4KIGU/ref=sr_1_4?dchild=1&keywords=milwaukee+ph+tds+meter&qid=1627929027&sr=8-4?tag=greenrel-20
I had one of these for a longtime
https://www.amazon.com/Milwaukee-Waterproof-Replaceable-Electrode-Resolution/dp/B007Z4GZHG/ref=sr_1_8?dchild=1&keywords=milwaukee+ph+tds+meter&qid=1627929137&sr=8-8?tag=greenrel-20
This is just PH, if you want to go the seperate pen route
https://www.amazon.com/Milwaukee-Instruments-Waterproof-Temperature-Pocket-Size/dp/B008932BNE/ref=sr_1_15?crid=14ITVMRGVR9AF&dchild=1&keywords=milwaukee+ph&qid=1627929315&sprefix=milwaukee+ph%2Caps%2C214&sr=8-15?tag=greenrel-20
I owuld try and find the multi-meter because, all electrodes die eventually, even with proper care (very important), wear out, and the MW801/802 has a replacable electrode. I also had an older model SM802 of the Multi-meter that was line green colored.
*Here is the replacement electroe for MW801/802
https://www.amazon.com/Milwaukee-Instruments-SE600-Replacement-Combination/dp/B007IT4EQM/ref=sr_1_5?crid=2XQ1OJV8BF5Q8&dchild=1&keywords=milwaukee+ph+meter+probe+replacement&qid=1627929672&sprefix=milwaukee+ph+meter%2Caps%2C201&sr=8-5?tag=greenrel-20
*This replacement electrode does not work for the old SM801/802 models.