G'day George, It's theoretically possible if the PCB P/N's of the SG and US/EU devices match, see here: [Only registered and activated users can see links. ]. If you don't know how to check the PCB P/N in the SG firmware please post a link to it and we can check it for you.
US/EU have possible PCB P/Ns of 105-01925-00; 105-01925-02; 105-01926-00; 105-01926-02; 105-01926-10; 105-01916-00; 105-02067-00; 105-02340-00; 105-02310-00 and 105-01982-00. Check which PCB P/N your device has in it's hidden menu 'Version Information' page by holding the battery symbol for several seconds and then press the screen's lower right hand corner/Next until you reach the page. If you have one which is the same as one in the SG firmware then a cross-flash is perhaps possible using one of the methods below.
Safest way to attempt the flash to SG is to use 'hybrid' firmware with the US/EU boot.bin and the remainder of SG fw, retaining the US/EU HWID of 2088. That gives the best chance to flash back if using SG is unsuccessful, however a full flash is also feasible but inherently more risky.