One of my first crushes was on that Silas in the 80s programme! 
It seemed such an exciting storyline at the time. He found out he'd been stolen by travellers as a baby, and tried to trace his birth mother. I've always loved the name Silas because of him, but I wouldn't use it for a child.
Have you thought about the Finnish name Lauri, pr Lau-ree, rhyming Lau with cow if that makes sense?