Ideas for weights/ calisthenics gift for 13 year old

[Mokeytree]

Looking for gift ideas for a boy who has fairly recently started being interested in calisthenics and weights.
He isn't into much else other than gaming so seemed a good idea for Xmas.
The bargain thread prompted me to get him a weights bench and adjustable dumbbells.
Looking for some additional ideas.
We do as a household already have a lot of stuff so tricky to think of things.
We have resistance bands, pull up bar, rings, barbell, yoga matt, block, ab roller, kettle bells.
Any ideas gratefully appreciated.
And if you can recommend a good book on calisthenics especially one with good photos and progressions that would be great.

Thanks all 🎄

Is he doing things like deadlifting/squatting heavy etc?
If so, you could also add smaller items such as wrist straps (figure 8 ones are generally good), knee sleeves, creatine, protein powder, to help support his form and strength.

@Bookaholic73 thanks for the suggestion but no he doesn't use the barbells. He mainly loves bodyweight/ callisthenics but has stolen some of my lighter kettlebells for curls and presses so dumbbells of his own seemed a good call.
I don't feel he requires creatine/ protein powders at this point.

Similar situation here and we got the mirafit tall parallettes which have multiple uses for calisthenics

Ah thank you I will have a good look later at what they are used for. Could be a good option if they open up doors to other calisthenic moves.