That's the risk we all take when we wear our watches.
Now that the scratch is out of the way, I say wear the crap out of it and don't worry ever again about getting it dinged up.
It's a Seiko, and Wabi-Sabi go hand in hand.
A few years back watch collectors started using the term wabi when talking about dirt, grime, and discoloration that old watches acquire. But wabi is not synonymous with crud. Wabi is better thought of as the feeling of sorrow, often felt when looking at something ravaged by time.
It is the same with our watches. Used daily our watches collect scratches, dents, and scars that weather them. It's bitter to scratch a watch, but it's sweet years later to see a scar and remember the fishing trip one was on when it happened. That's a shibui feeling.
Just like our clothes becomes more a part of us each time we wear them, so it is with our watches. The bumps and bruises they pick up over time become a record of our lives. Sort of like the lines on our faces as we age. That is what makes them, and us, unique. We may long for youth, for unmarred beauty -- but the imperfections add a quality of shibusa, or bitterness, that looked at the right way is paradoxically sweet.
You can read more here:
http://www.g-peopleland.com/wabi.html Don't feel so bad, it's unique to you now, and only you and those of us here know it struck a cast iron tub.