Where to find tires/tyres for SQ

[ccohen5 at compuserve.com]

So on looking carefully at the new arrival after its pre delivery 
track day, its Bridgestone 225/50/15 are looking worse for wear. I 
would like to replcae them with the spec. size which was 235*45*15 
which seems unobtainable on any web site in the US or UK.

I am trying to avoid a wheel purchase for the moment, so JIC am 
asking the list if anyone knows a source of this tire size.

The wheel size is 15*9J so I have to go with a wide tread tire to 
avoid stressing the sidewalls. If I can find a 245*45*16 it may 
help the over reading speedo as these are about 0.5" wider in 
diameter but means new wheels which I would be lucky to find in a 
width greater than 7J

Any help appreciated as always.

Colin