New York Community Bancorp. whose CRE troubles triggered a sector-wide selloff earlier this year, is the top takeover target among regional banks, according to Reuters' Starmine data analysis, which assigned NYCB a score of 98.

The bank trades at a price-to-book ratio of about 0.48, according to LSEG data. A ratio below one typically indicates an undervalued stock.

NYCB was followed by Valley National (VLY.O), Hope Bancorp (HOPE.O), Banc of California (BANC.N), Texas Capital Bancshares (TCBI.O), and Fulton Financial (FULT.O), whose assets range from $17 billion to $62 billion and all trade at a price-to-book ratio of less than one.

"If there is going to be stress and possible attractive valuations, it is going to be down the food chain in terms of the size of the banks," said Brian Mulberry, portfolio manager at Zacks Investment Management which holds several bank stocks.

Mulberry said that mid-sized lenders like Fifth Third (FITB.O), and Huntington Bancshares (HBAN.O), might have an appetite to snap up smaller rivals that would allow them to better compete with the likes of JPMorgan Chase (JPM.N), Bank of America (BAC.N), opens new tab and Wells Fargo (WFC.N).

The banks cited above either declined or did not respond to requests for comment.