The character in question is on this Yosegi puzzle box. It looks like it's using 貝 (かい / kai / shell / shellfish as part of the kanji. It's got what looks like 上 (うえ / ue / じょう / joo above / on)., or maybe the hi radical (匕).
The closest I can get is 貞 (On: Tei / Kun: sada) Tei being "righteousness / honesty / trust. Since this is on what looks like a Edo period depiction, the On reading makes sense. What's giving me doubts is that the right-facing arm appears to be going on a diagonal upward slope. So I could be completely wrong.
by Sproketz