HELP - which of the three places listed is likely to have boys belts

[saltire]

I need 2 plain black belts for saturday for the DSes, for a wedding to wear with their black trousers. Everywehre I have looked has been skulls and bright red/yellow/orange stripe kind.
We have a chopice of Matalan, Next or Mothercare, for 2 belts for a 10/11 year old and 8/9 year old waist

next would be my bet for most reliable option.

I would say next but the only place I could get my ds a belt like that was BHS.

The wedding is on saturday , We got their trousers and shirts from BHS, but the only belts they had were the kind that would be worn with jeans. I can't go into Dundee during the day because I have 3 mindees and can't cope with shopping on my own, never mind with 3 under 5's. The only places in the retail parks are the shops I listed and Tesco! That means dh go after wrok without needing to go into the city centre

Would snake belts do? There are some plain black ones in Next at the mo.

snake belts are fine, as long as they are plain black! DH will have to drive and get some tomorrow night! Thanks all