Hi welcome. What sources do you know about?
Does your Local Authority publish information about the parks & play spaces near you? eg. Bath & North Somerset have this webpage
Play and Play Areas
Are their any campaign or charity groups fundraising for play areas/equipment locally? How do they share the information that supports their cause?
The NCB's
Housing and the Health of Young Children makes the case for parents who live in flats without gardens who want outdoor play space that are safe (page 11)
ROSPA's accidents on children's playgrounds
Hth x