Are there sleep doctors on the NHS, Elaine? I am here in the US so I'm not as familiar with the system, maybe you can talk to your GP about a referral to a sleep doctor.
There is the Sleep Apnoea Trust in the UK ... while clearly their focus is on sleep apnea, RLS is also a sleep disorder and I wonder if they could either help you or point you in the right direction of someone who can. Start with a phone call.
Here's their website, looks like there's a location in Cheshire:
https://sleep-apnoea-trust.org/clinic-area/cheshire/
Just so you know, we don't have any personal connections to these clinics so I'm not sure if they are good, but it's certainly worth a try!
Best of luck to you. -Melissa, team member