Okay, I know that colors are one of the most difficult things to determine, but this stamp is really trying my patience. I even enlisted the fashion sense of my daughter. She states, in the images I've shown her off the internet, that this is a Scott 537b, but I don't know. I've seen so many color variants that I'm just lost. To me, it's violet with a hint of red, but of course it's a lighter color. I've attached a scan without any enhancements to it (other than cropping it). What are your opinions? 537? 537a? 537b? 537c?