They have replacements for all parts including poles. When we wanted a new set of poles, I drove to their premises in Alfreton and got them on the spot.
You will need to know the exact model and vintage of the tent though, they make minor changes from time to time. I took one of the old broken poles, if you don't have them it would be a good idea to take the tent itself to make sure you get the right ones.
Regards