The car has just failed an mot on a snapped rear spring

I have exe-tc coilovers

contacted exe- tc but sadly for my year of car they have lost the details of what spring is required and have nothing in stock

The spring is rated at 35kg with the smaller diameter end of the spring measuring around 60mm ID and the top end matching the original top mount.

if anyone could offer any advise on sourcing a replacement spring it would be greatly received

Rich