I have a set of those knives as well. The best reference for current value is Levine's Guide to Knives, 4th edition. These knives were some of the earliest etched blades done for BUCK by Aurum Etchings in Garland,Texas in '78 & '79. The latest values listed for them are: 501 - $70, 112 - $80, 110 - $100, 402 - $165, 401 - $175.
The real value is in what someone will pay. A 402 with the quail just sold on ebay this week for $165, so the book price would appear to be near on the money. Also, I was at the Dallas Gun and Knife show today and saw a slightly used 110 and two 112's with the deep etched game scenes marked for $75 ea. I haven't seen anything that gives a value for the wooden display case, mine has a special Buck Knives game scene casting, however, I don't have the sheaths.
Hope this helps some.
Doug
Lifetime member, Buck Collector's Club
"In HIS service."