There is an observance in Japan that you may find amusing - you are in a train station and see a couple. The man is in an all black, double-breasted suit, the woman in an all black kimono. The only way to tell is if the woman's obi is colorful, or solid black, and the man's tie is white or black. Blue and White are also prominent colors in Japanese fabrics and dishware. So many times, I hear western women moan about how the dishes they bought just won't match their color scheme at home.
Weddings use cranes, pine, and bamboo.
Oddly, anniversaries are not really observed like they are in the US, although any of the above would be most suitable, if one is searching for a symbol. If anyone has ever received a Japanese tea set, or glass-ware set, you probably noticed that you only received 5 cups, or 5 plates. Therefore in my book it is perfectly acceptable to say temari ball. However, we shall need expert advice on this and we'll have to await the return of Hayashi-san for final arbitration. Not an easy language, Japanese, and hardly surprising when they have 3 different alphabets and countless ways of counting, depending on what it is that you are enumerating.