The £45 million acquisition of Noble last November included rare coins firm Baldwin's and Dreweatts, an auctioneer of antiques and collectibles such as watches, fine wine and jewellery and which dates back to 1759.
Gibbons, which was founded in 1856 and has its main outlet on London's Strand, said the deal made it a major force in both dealing and auctions in the wider collectibles market.
It also represented a major step forward for its digital strategy as it looks to create a global online marketplace for collectibles.
Testing will begin on the trading platform next month, with an aim to launch the Stanley Gibbons branded online marketplace in the second half of this year.
In results today, the company said sales were up 16% for the six months to December 31 to £24.3 million. Trading profits rose 9% to £4.6 million.
The company said it has already seen some benefits in respect of cross selling rare coins between Stanley Gibbons and Baldwin's high net worth clients.
Gibbons added: "The stable returns being generated from the collectibles market at the same time as the falling price of gold during 2013 has resulted in some investors turning to collectibles as an alternative means of investing."
The period also saw the acquisition of Murray Payne, which is the world's leading dealer in British Commonwealth King George VI stamps.
Chairman Martin Bralsford said: "The enlarged group comprises quality heritage brands with leading reputations in their respective fields.
"When backed by the worldwide respect of the Stanley Gibbons brand and our financial strength and expertise, these businesses are able to deliver a superior auction service to both sellers and buyers."