Suitable toys for 8 y/o non-verbal autistic child?

Hi all,

My neighbours have two boys, both of which are non-verbal. They're obviously having a difficult time at the moment, understimulated as there's nowhere to take them, and I found out today local education services only give him one hour a day (there's just no spaces at the learning difficulties school due to funding shortages).

So, I want to buy some fun toys for them. But, I have no idea where to start! I had a good chat with father today re noise (yes it's highly annoying but I have Aspergers myself, went to a learning difficulties school and deeply sympathise) and he advised that he is quite destructive, can be aggressive, so obviously anything weighty that either child could brain each other with is out of the question. He likes to bang on things, so I was going to get him a wee set of bongos or something, but obviously after consideration wouldn't be suitable.

Hoping someone on here has some suggestions. I'm a musician starving for my craft (one look at my current waistline would reveal that to be a lie), seriously though I don't have a massive budget but could go up to £50.