The company has identified the Middle East and Asia as new markets for potential growth, but said expansion would require further investment.
It said that it would therefore examine its options, which could include the sale of part or all of the business, the BBC reported today.
The firm was set up by Edward Stanley Gibbons in 1856 and is the world's longest established rare stamp trader.
The company also sells coins and antiques, but is best known for its rare stamps business.
More From This Section
In April, it achieved a record for Indian stamps when a set of four featuring the portrait of Gandhi was sold for 500,000 pounds.
Only 13 of the 1948 Gandhi 10-rupee Purple Brown and Lake 'Service' stamps are in circulation. The block of four was sold to a private Australian collector for the highest ever price for Indian stamps, Stanley Gibbons had said.
Commenting on exploring new global markets, Stanley Gibbons said: "Unlocking this incremental long-term value is likely to require further investment and the directors believe that it is likely therefore that such value is best delivered either within a larger group or alongside a strategic investment."
On Friday, Jersey-based Stanley Gibbons said it had received an approach regarded as a possible offer by Disruptive Capital Finance.
Disruptive is led by City financier Edi Truell, a former pensions adviser to Boris Johnson when he was mayor of London.
Disruptive said that on May 31 it had been informed by Stanley Gibbons "that an email we had sent them was interpreted by them as an approach" under the UK's Takeover rules.
It added that it had been in discussions with Stanley Gibbons's management "for some time".