Sleep problems

Evening

I am new here. My 8 year old son has recently been diagnosed with ASD. 

He has always had problems falling asleep and staying asleep since birth due to allergies and reflux in addition. 

Despite asking for support all the way through his life none has materialized. I have tried so much to help him settle calm and reduce his sleep anxiety.

We go away from screens pre bed, bath, read, eye mask, fidget items, mediation and various  hand foot head massages.

Things have improved slightly as once he is asleep he stays asleep but it takes on average 2 hours from the end of bedtime routine  for him to go to sleep, so 3-4 hours and  his and my whole evening. He is tired next morning and I am exhausted too.

What can I do? Who can help? What's the verdict on weighted blankets? He gets hot and kicks sheets off most the time so looking for some first hand experience please as they can be expensive. 

Also i am surprised he hasn't been given the diagnosis of ADD too but I am assured from those who assessed our son that because of the cross over with ASD it doesn't matter. Does this sound correct? 

Thank you in advance for reading.