New Holland backhoe 555C tires

[Skally]

We have a 555C backhoe and need a new front tire. The current ones are Firestone 10.5-16. They are probably really old. I can't find a tire like this - not even in the Firestone catalogue. Can anyone advice me as to what reference I should be looking for or what the width is as I can't search the tire sites without all 3 numbers.

Thanks a lot