Heater matrix tubes

[Chicodelacurva]

Hi, my 2001 k11 has a coolant loss on the heater matrix. Both inlet and outlet tubes are almost completely dissolved as you can see on the pictures.

I've bought a new heater matrix online but it doens't include those hoses, I've checked the part number and it refers to the whole system.

Any idea where I could get those tubes? Thank you in advance.