I highly recommend the york bed company (google their number). I ve used them for most if my clients and for our king size divan bases/headboard.
They will use any fabric (if you send them the fabric you ve chosen) but you must ask them the quantity (meterage) you need.
Very good value for money given the quality (it is not high street quality), they deliver and assemble to London, leadtime 4 weeks.
I always their vi-sprung super comfi. From memory i pais ours £400 incl. Delivery.
I should have said Cant remember the price if the headboard as we added it at a later stage and i was pregnant whrn i organised and cant remember for 1 sec how much i ve spent I blame it on the hormones