Usually not worth the effort and prices. Try gun shops, pawns shops, egunparts, estate sales, garage sales, want ad, for sale ad, on line auction.
25 USD
RG model RG31 Caliber 32 long manufactured by RG industries, Miami Florida
See the link below. This will take you to the schematic for an RG 14 at the Numrich gun parts corp website.
20-60
No sn data available
FRG
25-50 USD or so
Inexpensive revolver made in Germany
SN's were not required before 1968
The majority of RG revolvers were very low value firearms when new. An RG 10 may be worth $20-50, depending on condition.
Best left to a gunsmith.
No serial number data base. Most of these were from the 1960s