Hans,

I would definitely use MIL 5606 fluid in your Matco Brakes. It is non-corrosive and very heat resistant. The red dye in it makes leaks easy to find.

For sealing your leaks use Permatex Pneumatic Hydraulic Sealant Part Number: 54540. It is available all over Europe but you may have to order it at your local auto parts. I can't recommend using teflon tape with the risk of pieces breaking off and wroking their way into your brake system. the last thing you need is to have a brake lock up. It gets really exciting if you lock a brake in a tail dragger.

John