AI live in London and couldnt find viva paper towel in here. Is there any substitution for that?

If you intended to use it to smooth crusting buttercream icing, you can get the same result with parchment paper

Any brand of paper towel would work so long as it's not textured.

you can use a smooth brand new clean cloth folded up a few times to give it body

have you ever gotten one of those really thick paper napkins in a restaurant

they are so smooth bet those would work great too