Dave, first I would try the NRA. Since it is a trophy rifle his name would be in their records most likely. They might also have listed his home town. If that is available do a search of his name for that location. If not him, it might turn out to be a relative.
Brad, try a internet search of the name. Also contact the his branch of service, they may be able to give you directions as to possibly find him. Try VFW groups for instance.
If you happen to get a general location, look up the county property tax records for the name. That may work.
Hope this is some help to the two of you. If you would like some help, send me a PM with their names and I will try and see what I can come up with.
Peace is that brief glorious moment in history when everybody stands around reloading.
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