Hi Gregg, my advise is to contact a dealer who sells the type of knife you are wanting to insure. Keep sales receipts and photo's of each knife (or get them all on video). As with any item like this you have to make sure you add a rider to you home owners insurance. Also, don't forget to make sure the policy covers your vehicle and any shows you might attend. If you do all this youll find it will get pretty pricy per $1,000. The other option is a great gun safe bolted to the floor. It will offer additional protection against fire. As once the heat gets over 400 degrees you can kiss the temper of the steel good bye!
Hope this helps.
Les