As ANZ scouts for plausible and affordable acquisition targets in Asia, one regional bank has, somewhat unexpectedly, come on the market.The controlling shareholders in Hong Kong's Wing Lung bank late last week said they would seek a buyer for their stake. The family of the bank's chair, Michael Wu, owns between 53 per cent and 63 per cent of the bank's shares (reports on this point vary).The bank has assets of about US$12 billion and a market capitalisation of around US$2.9 billion.Plenty of bigger banks in Asia may also bid for Wing Lung; basically all those banks that are rivals to ANZ for many of the regional banking businesses may consider it.Those already the subject of speculation include China's ICBC and Standard Chartered.