Children's flat cap & waistcoat (Harpenden AL5)

I’m on the lookout for a couple of bits for a school workshop for which the children need to dress as a “Londoner from the period of the Great Fire of London”. If anyone has stuff like a flat cap, waistcoat and plain long-sleeved shirt in size age 5-6 / kids that they’re turning out, please give me a shout! (I need to find two of each because I have twins... 🙄). Thank you!!