I have one like the Havel's but not that brand. I know I paid less than $3 for it. I had a tiny little one with the same type replaceable blade that I got at a quilt show like this one:
http://www.getcreativeshow.com/shirl...#Seam%20Ripper but it's so small I can't find it! I like the longer handle on the Havel type but my little one was good, too. I damage the fabric more with the other type ripper than the tiny razor blade type.