The 705 has a circuit and batteries in it yes ? Perhaps a metal detector could come in handy. If there is a local club of some kind, a member will more than likely be willing to come hunt for ya. Likely gratis, or for the price of a drink after the find.

I myself have recovered the following at request...

I pod from snow covered hill (tobogganing)
Wedding band at ski area
Knife under snow on a hunting trail

etc. etc.