225/45/15

[glh]

looking for 225/50/15 type r tires new or used

[Marsh]

You can have my used ones real cheap:

http://www.cockyracingguy.com/pictures/Misc/tires-02.jpg

The only tires in that size (that I know of) are the V70A Ecsta and possibly the Hoosier, however the hoosiers are actually made in old imperial sizes and stamped with a metric equivalent so they are often not the size that they are labelled.