One good and popular dataset is [Iris flower data set](https://en.wikipedia.org/wiki/Iris_flower_data_set) which you can also find under your link. It has been analyzed with PCA gazillion of times, just [google for it](https://www.google.com/search?q=fisher+iris+pca&tbm=isch) or search CrossValidated (see also links given by @ttnphns in the comment below). The first principal axis of this dataset is $$(0.36,   -0.085,     0.86,     0.36),$$ as can be found by the following Matlab code:

<!-- language: lang-c -->

    load fisheriris
    X = bsxfun(@minus, meas, mean(meas));
    [U,S,V] = svd(X,0);
    
    display(num2str(V(:,1)', 2))

Good luck!