The only place I've found Zinc Undecylenate food grade is Voigt Global.
I browsed the site briefly last night and didn't have the chance to read over order restrictions, policies, etc - but I believe they do have europe & australian distributors.
If you do a search you may be able to find them, but the US site is vdgusa.com - there are a couple 800 numbers - you may be able to get distributor information that way.