The main thing is that it cost much less to get MR2 from Japan than from Europe. That's why we've got more RHD MR2's. Nevertheless one can find LHD at about 5000 up to 6000 $ sw20 atmo, but actually really rare ))).
As for me, I bought mine for 12000$ 2 years ago. It's sw20 turbo JDM with some tuned parts installed, and it seemed to be really cheap.