Armchair covers

[shivvy]

I saw an episode of House Doctor today where it showed a plain white/cream cover for a sofa which seemed to have a couple of ties to tidy it up once it was put on the sofa. I would like to find something like this for 2 oddish shaped rocker/armchairs but am only finding very fitted ones or made-to-measure. I thought that they said the company was called mccord or mccourt.
Anyone know where I could get them?
Thanks