Breastpump Question

TamaraR4

When DD#1 was born, my county WIC office let me borrow a really awesome breastpump on the condition that I return it when I was finished.  Well, when I was done, and went to return it, the county told me they had just ordered all new machines and that I could just keep the one I had borrowed. 

My question is this.  I have replaced all the flanges and parts that milk touches, but do I really need to replace the tubing? Nothing touches it but air.  If so, where do I find generic clear flex tubing?