Hi Christine
If you're happy to post his name, then people here will be able to search the index online and be able to give you the correct reference numbers so you can order the certificate from the General Register Office at
www.gro.gov.ukAlternatively, you can register with the GRO and try to order his death certificate using the information you have and they will search for you.
Both services cost £9.25, if you have the reference despatch is 5 working days, if you don't have the reference despatch is 15 days depending on whether they find the entry or not. If they don't find the entry then your £9.25 will be refunded.
Hope this helps
Dawn