If Hudson's Bay wants to buy the iconic Macy's (M) - Get Report nameplate and its lucrative real estate, it better be prepared to open its checkbook.

Macy's could conservatively be worth about $16.4 billion, or $53 a share, points out Deutsche Bank analyst Paul Trussell. Trussell estimates that Macy's real estate alone is worth in the "low" $40 a share range.

Shares of Macy's spiked 6.4% on Friday to $32.69 on news Hudson's Bay approached the company for a deal, according to Dow Jones. Macy's market cap finished the session at nearly $10 billion, underscoring the disconnect between how the stock market views Macy's --only as a struggling retailer-- and how much real estate value is being trapped.

The news comes as outgoing Macy's CEO Terry Lundgren reportedly is becoming open to offers from potential friendly buyers as a measure to head off a board shake-up spurred by activist shareholder Starboard Value.

If such a deal does occur, it would reunite the Macy's brand with Lord & Taylor. In 2006, Federated Department Stores -- which later became Macy's -- sold Lord & Taylor to a private equity firm for $1.2 billion. Said then Federated chairman Lundgren, "After a thorough review, we have concluded that Lord & Taylor does not fit with our strategic focus for building the Macy's and Bloomingdale's national brands."

A spokeswoman for Hudson's Bay declined to comment on "rumors and speculation." A Macy's spokeswoman said the company doesn't comment on "rumors and speculation."