Black pyjamas for skinny goth 11yo? Please?

[PassataQueenofBritain]

Ok- DS is too small for adult sizes, even XS, he's very very narrow build, but gangly.
He fits about size 13 PJ's from John Lewis...but he wants black, plain black.
Has anyone any idea where to get plain black children's pyjamas?
They could have Metallica/Foo Fighters/Muse on at a push, but all the ones I've seen won't fit.

Ideas welcome please!
(And they don't actually have to arrive by Christmas, because his birthday is the week after!)

these

almost plain

I haven't seen any plain black ones, but if you popped the top of this set into the wash with one of those washing machine black dyes (and maybe the bottoms too so they aren't different shades of black) you would have a completely black set
www.ebay.co.uk/itm/Kids-Girls-Boys-PJs-Plain-Color-Stylish-Color-Cotrast-Pajamas-Set-Age-5-13-Years/152064151262?hash=item2367bacede:g:z90AAOSwNCtb3-tY&var=451264896727

www.amazon.co.uk/Dylon-Machine-Intense-Black-Powder/dp/B071LNN3XJ?tag=mumsnetforu03-21

Oh, thank you both! That's great. Will see when they're likely to arrive and go with those

www.emp.co.uk/p/home-wear-set/459149.html EMP is your friend here OP, for all your goth needs.

My dds the same (and will only wear boys pjs) we’ve mixed and matched black pjs from the boys section in primark before, she’s got a Calvin Klein pair in plain back - I’ve found similar on the next website but they’re a bit dearer than regular pjs - we got ours from a ck outlet if you have one near to you?
She’s also got a pair of Metallica pjs from h&m but sadly they’re out of stock now. Red bubble & emp have kids band tees if you wanted to pair one with black pj bottoms from primark, could be an idea?

Thank you!
EMP was my first port of call, but he's too small for the ones they have- his waist is so small, he's in age 7 boxers. He needs the trousers to stay up when he's walking around.