I had a look at the Avon website Paul but cannot see a CR500 in 175/65 15 size but if they do it that may be just the thing. The rear wheel has to work twice as hard on a 3 wheel car I suppose. My Yokohama Blue Earth original tyre is down to 4.5mm after just 3000 miles so its life will not be long. The choice of symetrical tread tyres in this size isn't great, going through the available options shouldn't take too long when the time comes.
