The nearest we have to an anthem is "God Bless My Home" which (for me) is a bit tuneless. Just to be really original and, to have a similar style anthem to "Never Walk Alone" and "Old Faithful" which make the hairs on the back of my neck stand up:-
I think a fantastic song would be "True Colours" (chorus only) - Eva Cassidy version. At the end of the chorus the words would be changed to "your true colours, true colours... are prim-rose and blue".
It was used for the Rugby Union World Cup but that shouldn't put us off!
Full chorus would be (with all flags and scarves waived in the air a la "Never Walk Alone" in fact the cue for the song could be the parading of the big flag):-
I see your true colours shining through'
I see your true colours, thats why I lo-ve you,
So don't be afaid to let them sho-www.
Your true co-lours, your true col-ours,
are prim-rose and bluuue!
see the link and start singing at the 37 second point
www.bing.com/videos/search?q=you ... ORM=VIRE4#
Anyone think this is worth a go?
sniff...sniff...sniffer