This could almost be a quiz - "figure out the set".

I had never heard 'cocopan' before, so a quick google image search confirmed it's a tipping or topper car.



The best-known Marklin one is the Red one included in many starter sets. But a "Brown Box" is also mentioned and like Tom I also thought of Mini-Club (Z gauge).



But, to the best of my knowledge there has never been a Tipping Car in Miniclub, certainly not one that I've seen.

And... except for VERY early starter sets (WWII production) no H0 sets with track have been released in Brown boxes (again, as far as I know).

So now I'm scratching my head as well.

If we are talking H0, then choices for Controllers are good. They are all 16V (AC) and you can get either 110v or 220v for the US market. Make sure you get one with a plastic case, White case is current and most recent production, Blue is older but so long as the case is plastic and not Metal you'll be fine.

If we are talking Miniclub, then of course it's 8V (DC), quite a different kettle of fish.

Either way, readily available on Ebay or a Marklin Dealer such as RJF, or maybe someone here who lives nearby you might have a spare to sell/trade.

Photos would help a great deal, or the numbers from the side of the loco cab. An approximate year you got the set would also help.

In the meantime, we can have some fun guessing!!

My pick would be set 3200 available from 1957 through 1974.



However the box would most likely be mainly Blue, although the late 50's boxes were a Red/Brown colour. Perhaps this is what you meant?



Hope this helps. If this is what you have, well done, nice basic set, will probably go forever and easy to get parts and maintain.

Cheers.

Steve
NZ