There are photos of the pH meter Ted used, but it does not give the name of the device. Where can I get one of these?
Mine is a no-name pH meters. So buying a no-name is quite difficult to you. Most popular electronic pocket pH meters in general quite acceptable for our use, since the pH is accurate to the nearest 0.1 pH.
I don't generally recommend any particular brand pH meters, but if I were to mention a popular pH meter, at least in the U.S.A. this would be Hanna pH meters. There is a good reason why I don't recommend particular brand, sometimes your local area don't have that brand and another brand might be just as good.
Usually your decision to buy pH meters at least for most people is the price or affordability. Accuracy for any electronic pH meters especially pocket ones are not important since most of them in the market is quite accurate for our purposes.