Thank you for your replies!
I will pick up some of the Pro C today and should hopefully get the seed mix tomorrow. I just really want Pippin to heal as soon as possible.
It's getting more and more difficult to get him out of the cage in the morning (I think he knows what is coming up). Also, he got so agitated today that he bit the vet and drew blood (he has never bit anyone before), I felt so bad for both of them.