FIE is/was an importer. Probably made in Europe.
15-50 USD
FIE.
10-100 usd
Probabably 22LR. Have it checked by a gunsmith.
Standard model, VG condition, $100, convertible model $150. Page 74, Gun Trader's Guide, 32nd edition.
50 USD
FIE was not a firearms manufacturer, but rather, an importer based in Miami, FL. They have been out of business for some years. They have sold several .38 Special revolvers. Titan Tiger (manufactured in Turkey) was one, and Standard was another. Some of their guns were made by Weirauch in Germany.
About $100 if operational. FIE was an importer of moderate cost firearms, mainly from Italy and Spain. No high collector interest.
25-65 US dollars
While the name Regent was used by several companies, the most common (and recent) was an inexpensive European revolver imported by FIE of Florida. These were of dubious quality- values run about $25-$75. They have not been imported in some time, parts are very hard to find.
Numrich Arms website has expoded view. e-gunparts.com