In my area, Specsavers hold the NHS contract for age related hearing loss under the new NHS commissioning regime. You can therefore be offered an free NHS appointment at Specsavers. You can get appointments almost immediately, rather than waiting at least 6 months for the hospital in my area, and at any Specsavers with an audiology department, so at a time and place usually more convenient to you.
I have NHS hearing aids from Specsavers, they are exactly the same as you get elsewhere on NHS and you get free batteries, tubes and repairs etc just the same.
I'd check with your Doctor as to whether your area is included in the Specsavers scheme or check here
http://www.specsavers.co.uk/hearing/hearing-aids/nhs-hearing-aids