There are lots of tire threads but things change sometimes. If you upgrade to 14" wheels/tires then you can get the new Goodyear Endurance tires
that are now made in the USA but they don't make any in a 13" size.
We have 14" Carlisle radial trail HD tires
on our 16' Scamp
, but they also have them in the 13" size you probably have. They have an 81 MPH speed rating, which I hope means they are built a little better than the average Chinese tires on the market today.