Hi,
Anything posted or couriered to you from another country goes through customs to check it is not banned or restricted and you pay the right tax and ‘duty’ on it.
This includes anything new or used that you buy online or buy abroad and send back to the UK.
The parcel or courier company (for example, Royal Mail or Parcelforce) is responsible for taking goods through UK customs.
You’ll be contacted by Royal Mail, Parcelforce or the courier company if you need to pay any VAT, duty or delivery charges (‘handling fees’) to receive your goods:
Tax and customs for goods sent from abroad
To check the customs charges and rates, please search commodity on trade tariff UK.
https://www.gov.uk/trade-tariff
You can enquire about Home Office for requirements and legislation by emailing public.enquiries@homeoffice.gov.uk.
https://www.gov.uk/guidance/import-controls-on-offensive-weapons
Thank you.