Had it been opened?
I remember my dad opening and eating (with no ill result) a can of ham sent over from the USA during WW2. This was in the late 60's!
Just give one of them a squeeze, and see if you can smell anything. They will probably have lost some fragrance, so you could just double up on the number quoted in your recipe.
I wouldn't bother with it, melv. It'll be like putting hay in your dinner.
I remember Fine Fare. I think it became Somerfield, didn't it? Which also doesn't exist now.
Generally speaking I'd go with Atalanta suggestion. However, after 30 years you may as well and collect a few dry fallen leaves from the trees for all the flavour this bouquet garnish will impart.