I'm looking for a Toyota MR2 Spyder and almost all of the advertised cars were build in either 2000, 2001, and 2002. For example, out of the 22 Spyders that are currently on GumtreeCars and carsales, only one is less than 18 years old. As I understand it, Spyders were imported into Australia until 2006. Does anyone know why?

MK3 USA sales progressively dropped over the model life. They sold 10x as many in 2000 vrs 2005. So Id expect to see this repeated in the qty of cars of each year being offered for sale. I can't find OZ sales volumes but I imagine they would follow the USA data.
 
https://mr2wiki.com/AllMo...dwideProductionNumbers

Yeah, the pattern of the number of cars advertised on these site somewhat follow the pattern of the number of cars sold in North America.
 
Build Year  No. of Adds
2000         11
2001         6
2002         4
2003         0
2003         1
2004         0
2005         0
 

Is there a feature or issue in the early cars that your trying to avoid?

The rubber parts like hoses, window seals, etc. would probably be in better condition on the later cars. If the six speed gearbox on the later cars have closer ratio, a six would be nice, too. 

I had a look at a 2005 ZZW30 today and it has the C65M transmission. So it doesn't have the close ratio boxes that are in the Elisa, Celica ZR and Corolla Sportivo?.