UPDATE 1-Codere core shareholders say could sell stake

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MADRID, Sept 29 (Reuters) - The majority shareholder in Spanish gaming firm Codere (CDRE.MC) is studying possible options for its 71 percent stake, including its eventual sale.

In a statement to the bourse regulator CNMV on Monday, Codere said the Martinez Sampedro family will make a decision on the stake on or before Oct. 31, which is the deadline for a payment of 188 million euros ($269.8 million) to the former Codere owners, the Franco family, for a 41 percent stake in the gaming firm.

Earlier on Monday a source close to Codere, referring to the terms of the purchase of the Franco stake, told Reuters: "As the deadline for the payment is not yet up and everything is up in the air (the Martinez-Sampedro family) is keeping its options open".

Under the terms of the agreement, the source said that if the Martinez Sampedro family does not make the payment, it will have to renegotiate its debt or otherwise a mechanism will be triggered whereby the payment is guaranteed through the sale of the shares.

In a research note, Ibersecurities flagged Ladbrokes (LAD.L) or Greek gaming company Opap (OPAr.AT) as potential buyers for the stake.

Asked whether Opap had had any contact with Codere or was interested in a stake in the firm, Opap Chief Executive Christos Hadjiemmanuil told Reuters: "We will not comment on that". (Reporting by Rodrigo de Miguel, Raul Tebar and Judy MacInnes; Editing by David Holmes)