You can view the ISRC assigned to your track via “Your Music" page.
Once logged in to your Record Union account. At the top right corner click Menu(≡) > Your Music > Submitted tab and all of your published releases that have not been taken down will be displayed. The tracklist for each release is displayed on this page as well. Go to the specific track in question and you'll find the ISRC right beside it.
Please see the images below for reference.