If you dont care what tank model you get anything is a available.
If yiu have speficic models in mind then we can point you in directions. Say you want a t90. Henglong is your only bet.
if you want a sherman there are lots of options from cheap to expensive and kits.
if you want a tiger, same thing, everybody makes one.
I
M1 Abrams, theres two, cheap henglong which is pretty good as a toy, or to start upgrading, then the 1100 dollar super computer equipped kit that tamiya makes.
It all depends on what tanks you want and what you want to do with them.