There aren't really any I know of that don't have a subscription. I know about Fi, Tractive, and Halo as GPS collars, but they all require a subscription.
It depends where you are - I live in a city and was also looking for a tracker with no ongoing fees, and ended up going for an AirTag collar. It uses the Apple AirTag to send updates for where your dog is. It's good in larger cities with lots of Apple devices, but not as effective in rural areas.
It's worked relatively well for me (granted, I've never had to rely on it to find my lost dog), and it's definitely better than nothing. Doesn't require charging or other hassles, so works well.
If you are looking for a proper GPS tracker, I'm afraid most (if not all) of them have monthly fees.
------------------------------
Jerry McNulty
Founder
Paws and Whiskers
MA
------------------------------