How do you intend to ship this caviar? Apart from the safety issue (being very expensive) it is a biological substance and therefore requires time-critical delivery. I also found this on the FedEx site:
Export Prohibitions and Restrictions
There are some items that are forbidden for export by Customs from Russia. These items are in addition to items prohibited by IATA.
Forbidden for Export from Russia
Birth certificates
Cash and cash equivalents
Dangerous Goods as defined by FedEx IATA
Food, perishable
ID cards, including military IDs
IOUs and cancelled checks
Liquor
Lottery tickets
Minerals, ores, semi-precious stones such as amber,
or the goods bearing them
Narcotics
Paleontological samples
Passports
Printed or audio materials potentially harmful to Russia or its citizens
Russian Federation workbooks
Salmon or sturgeon caviar, crabs or crab meat
Soil
Stocks and bonds
Weapons such as knives, ammunition, and military equipment
Are these canned or sealed in special containers to prolong shelf life? How will you ship them? Customs authorities might want to see some paperwork such as a valid CITES export permit as mentioned on page 12 here:
https://www.cbp.gov/sites/default/files/assets/documents/2016-Apr/icp011_3.pdfAnd of course it goes without saying that escrow is a must for this kind of transactions. I hope you agree with this basic rule, OP.