1: The Chassidishe Gatesheader’s suggestion of Gateshead
2: Lakewood NJ
I don’t see the Five Towns for someone who has children & no support. You will have to find an apartment that can fit your children, which will be expensive (I would think), and will just add stress to you family (which is probably already stressed). I agree that if money was not an object, then the best place for a special needs son is in Darchei.
Both Lakewood & Gateshead (from TCG) have cheap housing (Lakewood has huge basements for under $1000), cheap tuition, and support for special needs children.
Alternativly, you can consider joining the Chardal community in EY (or Dati Leumi). I don’t know much about it, but they might be more accepting of your children.