Who can repair an old Apple keyboard?

I have a wireless extended keyboard dating from several years ago. In recent months when I switch on my iMac, wireless mouse, and keyboard I get a message "Keyboard not connected." I've had to go to Bluetooth, click the "Keyboard not connected " under Devices, then switch the keyboard on and off several times before I see "connected," or sometimes numbers to type in and press Return, in order to connect.

I decided to buy a new keyboard from Apple. But this is slimline, not as wide as the extended keyboard with raised keys, with the keys in slightly different positions, It has proved hopeless when I touch type, which I could do with speed, on my old one.

Do you know anyone who can repair my old keyboard with its raised keys?