* HSBC has opened its books to possible suitors -source
* Brokerage likely worth C$200 mln - C$300 mln - source
* Analyst says more than one firm likely looking (Adds byline, details, background, comments from portfolio manager and financial services executive. National Bank declines comment)
By John McCrank
TORONTO, Aug 22 (Reuters) - HSBC Holdings PLC (HSBA.L) is in talks on the possible sale of its Canadian wealth management unit as part of the banking giant's worldwide restructuring, a source with direct knowledge of the talks said on Monday.
The London-based bank has given potential bidders access to the books on its Canadian retail brokerage, which the source said manages around C$16 billion ($16.3 billion) in investors' money.
"If that business were to be sold it would be somewhere between C$200 million to C$300 million," said the source, who was not authorized to speak on the matter.
In a report on Monday, Canada's Globe and Mail newspaper pegged the unit's managed assets at about C$30 billion.
A spokeswoman from HSBC Canada said the firm had no comment on the matter and that it does not disclose the value of its Canadian assets.
The financial statements are now being reviewed by at least one interested party, and a formal deal could materialize soon, the Globe said in the unsourced article it published Monday.
Although no suitors have been formally named, National Bank of Canada (NA.TO) is believed to be in the running, the paper said.
A National Bank spokeswoman declined comment.
"National Bank totally makes sense because of their location and need to grow," said Tim Logan, a portfolio manager at Cockfield Porretti Cunningham in Toronto.
National, which operates mainly in its home province of Quebec, bought the 82 percent of wealth management firm Wellington West that it did not already own in July for about C$273 million to expand its presence in Western Canada.
"The Wellington West purchase demonstrated an interest in accumulating assets in the Western provinces, so HSBC would be additive to that," said Brad Smith, an analyst at Stonecap Securities.
National also stands out among Canada's "big six" banks as the only one without any notable foreign operations, leaving it constrained in Canada's highly consolidated market, where options to expand are few.
"The knock on National Bank has been no way to grow, because it's in this captive little market," said David Baskin, president of Toronto-based Baskin Financial Services. "I suppose this would be an interesting way to increase its assets."
Baskin said he had no knowledge of any deal in the works.
Shares of National Bank were down 0.4 percent at C$70.06 on the Toronto Stock Exchange on Monday afternoon.
HSBC has the largest Canadian presence of any foreign bank, and the sale of its retail brokerage would continue the trend of foreign players giving up on the Canadian market.
"It's a tough nut to crack. The Canadian banks are so entrenched, and it's hard to take market share away from them," Baskin said.
Last week, Bank of America (BAC.N) agreed to sell its $8.6 billion Canadian credit card portfolio to Toronto-Dominion Bank (TD.TO). One year ago, Citigroup (C.N) sold its $2 billion Canadian MasterCard business to Canadian Imperial Bank of Commerce (CM.TO).
Other possible suitors for the HSBC assets include Richardson GMP GMP.TO, Macquarie Private Wealth, Canaccord Genuity (CF.TO), and Desjardins Group.
Desjardins, Canada's biggest financial co-operative, has said it plans to build up its presence west of its home province of Quebec, mostly through organic growth but also via add-on acquisitions.
Desjardins is already expanding its insurance offerings through its C$443 million acquisition of Western Financial, the largest property and casualty retailer in Western Canada and the fourth largest insurance broker in the country. Western also owns an online bank.
"I would not think it's just one firm looking at HSBC's domestic brokerage business," Stonecap's Smith said.
"Financial services in and of itself is a game of scale and so that would mean that many players that thought that they could provide good service to HSBC clients and to their advisers would be remiss in not taking a good hard look at it."
HSBC Bank Canada's core personal banking operations are not up for sale, the source said.
$1=$0.99 Canadian Additional reporting by Pav Jordan, Cameron French and Euan Rocha; editing by Peter Galloway