If your total vehicle payload is 700 lbs you do not have much to work with.
If family and camp stuff use 300 lbs you have 400 lbs left for Tongue weight.
That means about a 3000 lbs TT.
You will most likely exceed your axle weigh capacity, before you exceed your towing capacity.
However, if your 700 lbs is the weigh of everything you load onto your TV. Subtract that from your TV's max cargo, which is usually posted on the door jamb.
Then divide that number by .13 for the percentage of tongue weight. That will give you the loaded TT weight (not the dry weight) of the TT you can haul.
Let us know what the number tell you.
Good luck