Care of old baking tins

Day to day cleaning
Wash your tins in warm soapy water, and clean with steel wool (Steelo).
Dry in a preheated 130C oven, turn oven off and leave tins in for two hours.
Twice a year rub cooking oil over to prevent rust from occurring.
Do not place in a dishwasher as this will make them rust.

Cleaning stained tins
Create a paste of baking soda and warm water.
Apply the paste to the tin.
Allow to sit for 10 to 15 minutes.
Scrub the paste into the stain using steel wool.
Wash the tin with warm, soapy water, following the instructions above.
Repeat the process if necessary.

To remove rust
With the dry tin, using a dry steel wool pad scour the rust from the tin.
Wash and dry as above.

I chose to deter away from Teflon bake ware after being aware of the slow breakdown of the Teflon and the possible implication on health, plus the on-going cost to replace it. Being of a reasonable age myself I had a couple of Bonco and Willow brand tins, so sourced my remaining bake ware through Trademe. Another option is to suss out your local second-hand shop.