Apologies, I'm from Australia. Thanks for the link and advice, which points to this - https://buy.garmin.com/en-US/US/maps/on ... 16482.html
I previously checked the Garmin.com / Garmin.com.sg / Garmin.com.au sites prior to posting my enquiry. The 3592 is not available in either US or Australia. While the closest version from US is the 3590, hence my question on where I should be buying a "compatible" map from.
Go to this link : http://www.garmin.com/us/dealerlocator? ... 0-D1257-00
In dialog box, for :
Choose a Dealer Type : Choose Automotive from pull down box
Enter City, State, Zip Code : Australia
After a while you will be prompted with a list of Garmin resellers in Australia.
Choose one closest to you and give them a call for your need.
I believe all Garmin Maps will work with any model Nuvis
Unit 3592 is from the 35XX family but localized for Sin-Mal use ... Junction View/Lane Assist feature only works with Garmin Sin-Mal with these units
If same scenario is with Aussie maps, then JCV & LA assist feature not available should you use this unit there with Aussie Map. Other than this map should work.
Suggest you enquire with Garmin resellor folks there