Any business studies student will tell you that you cannot re-create anything that has been copyrighted unless you have 100% rights to use their branding. Another simple law that has been practiced again and again in all GCSE business studies lessons:
The law gives the creators of literary, dramatic, musical, artistic works, sound recordings, broadcasts, films and typographical arrangement of published editions, rights to control the ways in which their material may be used.
Do you have the FULL consent of dukes to use their name? I highly doubt a company running for 250 years will let a 17 year old kid have the full right to use the dukes branding!
Also, mikes comment:
"you cannot reproduce someone else's brand name, image or trademark or copyright materials for any purpose."
This is also true. Are you sure you paid attention in business studies class or did selective hearing take over?