Having been in the leather restoration business for 10 years or so I have tried many products. First off let me say I would not recommend using any leather cream if it is not absolutely needed on a vintage leather item. Easy to put on, impossible to get off. Consider carefully before you do it.
The finest product I know of is Connoly's Hide Food. It is primarily lanolin. Smells like leather, is not sticky, disapears at room temperature and shines nicely. This is used and made by the British for Jaguar and Roll's leather car seats.
For those who are interested..Pecard's is a petroleum wax and is the nastiest goo on the Planet. do NOT put it on vintage leather if you value it.
It is made for boots and shoes in wet weather. For this purpose it is fine. It will destroy your leather collectables.
As for spending any money on this frog I would hesitate to do it myself. Leather restoration is expensive and mostly reserved for high dollar items. One of the things to steer clear of is shoe repairmen. They are primarily interested in serviceability and not restoration. I have seen many valuble leather items ruined because the owner took it to a shoe repairman.
This one needs to have the rivet removed, the piece restitched and another rivet hand hammered on. A competant repair/restoration would cost around $35-40 bucks plus shipping and the piece is probably not worth much more.
Think before you attempt to improve on any collectable...Jerry Burney

lugerholsterrepair
Yuma, AZ 85367