There is no easy answer to your question...
I always preferred Friulmodel but yes, they are expensive.
If you really want plastic, the best second bet are Modelkasten. Easier to assemble, plastic, BUT also pretty expensive.
Most Dragon kit have link & length tracks (unless you pick a kit with their patented DS rubber tracks. Nice, but more difficult to sack over the wheels).
You could also google for Hobby Boss track links. Very nice and way cheaper:
The Pz III, Pz IV, Tiger, etc... all had different tracks and most had early and late within their type.
Hope this helps.