Weighed animals are also an option. Weighted Animals are a wonderful and cuddly way to assist with sensory regulation for children and young adults living with Sensory Processing Disorder, Autism, ADHD, ADD, Anxiety and Restless Leg Syndrome. They can be very helpful for kids who are unable to sit still in their chair, are easily distracted, or unable to focus on the task they have been set. They’re also great for calming down before bed!
https://www.thetherapystore.com.au/product/weighted-animals/

Since he piles things on his lap I would go for a weighed lap bag. I bought recently one for my daughter at the Therapy Store;
https://www.thetherapystore.com.au/?rf=kw&kw=Weighted+Lap+Bag+-+Sequin

Try a local support group maybe!!

there are some good comments here

Did you find a good one?

Local support groups should have tht information. Maybe a local stay at home mum that makes them.

Maybe try asking a local support group as they may have some good recommendations from their experiences

Did you decide whether to get one or not?

what did you choose?

Do some research on the net and also try looking on ebay.

What did you end up choosing?

Really hope you get to find some

Speak to your OT if you have one, or phone your local occupational therapists in your area they might be able to order one for you at your own cost. If you are handy with a sewing machine, you might be able to find a pattern online to make one yourself, my son who is on the spectrum is really fussy with colours and fabrics, so get something your son would be happy to put on.

see your OT ours was so helpful and we got a deal for ordering a large order

Occupational Therapist’s can order them for you too, otherwise are you registered with an association? We are with Autism SA and they are great about helping with enquiries and providing information.

I actually just seen a post last night on a facebook page talking about where to buy them the page is called Bumpy Land

I’ve never heard of this, but find it really fascinating.

I got mine cheap on ebay. It came from the UK and only took 8 days to arrive.

doing a search on the internet should bring quite a few up. I’m thinking of getting one for my little girl who has dravet syndrome a catastrophic epilepsy that is uncontrolled, most children like my daughter have sensory problems and dont sleep very much so im getting to the point of trying anything to help her and the rest of the family get a good nights sleep. If you have an OT you could ask them to help you find one that you think would be helpful. Good luck hun.

sorry I have never heard of them. perhaps ask the autism society???