EVs are expensive because of the battery.
A cheap car is not a novelty, specially for asian manufacturers. There is no cheap EV because there is no cheap big ion-li battery.
Toyota strategy of focus on hybrid and hydrogen seemed weird to me. But over the years has been started to make sense.
The world needs a better battery. Until that, EVs will be heavy and expensive.
I don't know any product that matches your requirements.
If I had to deal with that today I'd buy a rasberry pi, a USB sim card dongle and some raspberry hat with GPS receiver.
You can write a small API that listens to the raspberries, who sends periodically their positions, and save it to a database.
But it's a quite large project. There's a lot of aspects to consider. The GUI, security, batteries, and a way to attach it to an animal without being lost or destroyed.
Sorry for not giving a useful answer lol. If you come out with an actual solution I'll be glad to hear it, so I can track my cats in case they get lost.