Ink and watercolor, 2014
The original is being auctioned to help Usagi's creator, Stan Sakai. 9 days to bid on it and take the piece home and help out on a great cause at the same time.
Details of the auction here.
This artwork will be published in the upcoming Dark Horse Comics special book, "THE SAKAI PROJECT; Celebrating 30 Years of Usagi Yojimbo", Being release in July, 2014 (at San Diego Comic-Con) with all proceeds also going to Stan & Sharon Sakai.