I completely agree with your sentiments on finding the right car in the UK. Apart from a small handful, there are no nice RX-7\'s for sale. Most are the remains of what were a cheap import some years ago.
Importing and whilst buying from Japan. The Japanese commonly refer to monetary values as hundreds the ambiguity of the 2 million yen as being 200.
The prices on carsensor are massively inflated - I say this with huge experience of importing cars and I have been monitoring the site since it\'s inception. Carsensor is purely Japanese Domestic Market (hence tax inclusive prices which you do not pay for export) but you will still find trash on there. Most cars however, are not and the price is reflective of this. There are bargains out in Japan - dealer part exchanges / private sales if these do not find themselves transiting through the auction portals then you can make an exceptional purchase. It really is a case of looking in the right places.
The days of cheap imports is also well and truly over. I started by purchasing at a rate of ¥180 to £1 during 1996/1997 followed by a gradual increase with the peak being circa ¥250 to £1 in 2006. Now in 2010 you are looking at a rate of ¥130 to £1, so you can imagine how the price of cars have been affected drastically. The current yen rate has been stagnant since 2009 partly down to the Yen losing it\'s fixed term with the $ - there are no signs of a recovery.
A fresh import and one chosen to specification will almost always be more expensive than most of the cars for sale in the UK. One simple reason is that it is far more worthwhile for an importer to bring in a cheap and perhaps even an aesthetically unpleasant car which would yield the same return as an expensive unit. Also because there aren\'t many who would be willing to stump up and pay top money for a well sorted RX-7. In my experience, I have seen a lot of people purchase cheap ones only to be left spending more on putting things right than the outlay of an already sorted car from the outset.
There a lot of RX-7\'s in Japan that wholly justify the >£20000 price tag, I myself have been guilty of this on a few occasions but with no regrets. These cars have a sterling heritage in Japan often seen as a true testament of the finest sports car to have ever come out of Japan.

Freddy