I am beyond impressed and a bit jealous.
If you want to go subtle, you could do team colours for invites or decor
-red, orange, brown
-blue, cream, grey
Wait. Invites based off the Sandvich poster. Unf. Anyway
There are probably people you can commissions to do invites somewhere on this wide Internet. Someone else would probably have to speak up for that.
Just a note. I think this would be best in /dis/ if only for the fact more people might see this.