I've been doing online newspaper searches the last weeks towards my next book (a history of theatre and performance in modern Indonesia). Yesterday I used an Australian site- http://trove.nla.gov.au/newspaper/. One of my searches, on keroncong, revealed an article about a 1954 visit of the Queen to the Coocos Islands. This small island chain, today part of Australia, is inhabited by 500 "Malays" and 100 people of European descent. The Malays, it seems, originate from various parts of Nusantara, brought there starting in the early 19th century to work on the island's coconut groves. Their music in the 1950s was described as a mixture of kroncong and Scottish "foursome reels".
An online video (above) shows that today their music (and ceremonies) is much more Malaysian than Indonesian - the result it seems of Cocos Islanders working in Malaysia and marrying Malay women in recent decades.
What a fascinating ethnographic site this would make!