Try Camskill for your tyres and have a local place fit them for you. They usually charge about £10 per tyre or less, including valve, balancing and disposal of the old tyre. This is always cheaper for me than Blackcircles on like for like tyres.
http://www.camskill.co.uk/
Linglong Greenmax (don't laugh) are excellent tyres, quiet and very good in the wet on my Honda Accord, but may be different on a 75/ZT:
http://www.tyrereviews.co.uk/Tyre/Li.../Green-Max.htm
I had Uniroyal Rain Experts on my Saab 900 Turbo and they were brilliant. Unbelievably grippy and still quiet. Its worth bearing in mind that a tyre's performance is very changeable when fitted to different cars.