There are plenty of imported cars here already. My GT hardtop was imported in 1997. It won't have been the first and they have been coming ever since. Finding a local car gives you more inspection options, rather than being reliant on the auction grade on a 26-36 year old car in Japan.
How handy are you with working on cars? A car that does not need work is likely to be cheaper overall.
A car that drives is more fun for most people than one that does not drive at all.
I'm doing a 2GR swap now in my storage unit, and I'm spending a lot more than $7k on it. With the Frankenstein headers and Wilhelm X-pipe system, you are looking at USD$4k+ after shipping. In the US, where the engines are cheap, a full-service swap starts at USD$10k from shops who know exactly what they are doing. I expect the V6 swap will make it is nicer car for me, but different people like different things.
For a 3SGE swap to a 3SGTE, you also need to find a decent transmission. Not all second ones are that nice to use.
The T-tops have new seals available, so leaks are not a big deal. Having a sunroof vs a little more mass is not a big tradeoff. If you are very tall, then there is a reduction in headroom. Different seats and rails are a relatively expensive fix for that.
How will you drive it? A car from 1994 onwards has had all of the suspension tweaks Toyota came up with. So they are more forgiving to your inputs if you go a bit fast into bend that then tightens on you. The suspension may need a refresh, with new bushings etc, but will drive as intended. Cars that have been lowered may have roll centre adjustment blocks that can then create bump steer issues. Lots of toe-in can calm that down, but then spoil other factors. Buying a turbo can give you an old-school turbo soundtrack (mods for little cost) even you are not driving quickly.
If you are not extremely tall, I'd suggest looking for at one such as the 1994 Bathurst for sale in Dulwich Hill, NSW for $23k. As an unmodified car, it is the most likely to hold its value, so if you decide you want something different, it easiest to change. Not all Bathurst models had air conditioning, which may be important to you in Queensland?