Thanks for all your replies. We have asked the "care agency" to find candidates for us based on the following job description. Will keep you in touch with how things go.
1. Visit for 3 hours, twice weekly. One weekend visit. From 12:00 to 3:00 pm
2. To feed Mum her lunch on those visits. This includes cutting up Mum’s food, and spoon feeding her. If she wanders during her meal, take food along and settle her somewhere else to eat or persuade her back to the dining room to finish
3. Play music, and possibly sing with her in her room. We provide CD and music that Mum likes
4. Walk with her, if possible take her walking in other wings of the home for change of scene
5. Take her down to lobby café for special cup of tea and something to eat (home provides selection of items)
6. Be kind, hold her hand, hold her arm when walking, be her “special person” in our absence
7. Be observant of what is going on in the home
8. Check in with Ward Nurse to see how Mum is doing, weekly
9. By their twice weekly presence at the Care Home form good working relationships with care staff and relatives of other residents
10. Send brief email to Mum's daughters weekly
11. Occasional telephone calls with daughters, as situation demands
12. Meet with us (briefly) when we are in UK visiting mum