Apologies for tardy response.
Having a bit of trouble finding someone for this job, I imagine there must be one or two print specialists producing these patterns - next time I go into John Lewis will be sure to check out the haberdashery department to have a look for clues!
Via the very helpful @Print_procurer on Twitter I was pointed in the direction of Sweden's Billes Tryckeri www.billes.se.
Hope this helps.
I'll keep on looking for other potential printers in the meantime.