At the NEC I saw that Blockley now do 15in radials in 165, 185 and 185/70. The first would go on an early Flavia, the latter is what I used to run when I had an Aurelia. The company have an excellent reputation for their tyres for road and race tyres for prewar cars so I'd trust the quality. They've made them to a VR rating - 150mph.
http://www.blockleytyre.com/page2.htmDavid