General :: Copy Wildcard Files From Directories For Matching

I have 2 massive duplicate dirs of the same format as below:
dir1
subdir1
file1
subdir2
file1
subdir3
file1
...

Dir2 is the same, but it has some newer files of the same name. I want to copy all file1's from Dir2 to the same name and folders in dir1. So basically something like:
cp -pr bkpDir1/*/*-big.gif Dir2/*/*-big.gif

This works for singular cases:
cp -pr bkpDir1/uniquesubdir/*-big.gif Dir2/uniquesubdir/*-big.gif

But not for wildcards:
cp -pr bkpDir1/subdir*/*-big.gif Dir2/subdir*/*-big.gif

Anyway the aim is to do the first cp above, I have tried a few options using find. In trying to show an example stumbled upon a way that worked, while in dir2:
find */*-big.gif | xargs -i cp -rp {} ../dir1/{}
Sure there are better ways also...