Replacing my sons 18th birthday gift

Totally gutted my sons 18th birthday gift his moped was stolen whilst visiting his grandparents found next day burnt to a crisp. Not only has he lost his bike hes lost his independence he suffers from complex needs having his own transport was a huge step for him to achieve he worked through doing his cbt test and passed whish I was so proud of so for his 18th he asked for a moped you want the best for your kids I let him pick what bike he wanted and I worked to get it for him. Unfortunately it got stolen and destroyed someone stolen it for 1 night of fun is it really worth it considering the damage and stress its caused I had it insured but im left with a £450 excess not knowing what im going to get back and now his insurance is going to go up all because someone thinks its OK to take someone else's belongings and destroy them. I just want to get his confidence back and try to get him back on the road again these times are depressing and stressful enough and with Xmas round the corner any help would be appreciated its embarrassing having to ask for help and its so frustrating because its someone else's fault many thanks in advance.