Advice regarding medical equipments suitable for child with CP

Hi all.
Iam new here and as my nick name states- I am trying to help. 
I was recently abroad and met young girl who suffered brain damage during difficult birth and was diagnosed with CP. She's now about 6yrs old. I was horrified to learn her family isn't eligible for help with equipments she needs. Her mother (she's extremely attached to her) has to carry her everywhere as they cannot afford the wheelchair etc. And this is where I need your advice. I am planning to set up a go fund me page to buy wheelchair for her. I've seen many second hand advertised on internet,too. However, I am not sure what would be suitable? She needs head support,too. Please, let me know if you have some to recommend.
I feel very sorry for them as they had to fundraise to send her abroad for treatment as the one available in her country is stone aged...

Any suggestions regarding other equipments that are helpful are gladly received.

Thank you!