On the SWA (square wheel arch) cars you're pretty limited to about a 13X5" or maybe a 5.5" wide wheel and a 175 size tire. Moss has 13X5" Minilite replica wheels for sale and you can also get similar wheels from a variety of other sources. There is a new style wheel that has just come on the market here in the US for the Midgets as well made by Performance Superlite in Australia and sold through Acme Speed Shop here in the US that you might like the looks of as well. Check them out at http://www.acmespeedshop.com/index.html . I don't see the photo of the new style wheel posted yet, but one is shown at this site http://www.mgexperience.net/phorum/read.php?3,920042
Hope this answers your wheel questions.
'73 Midget (V6)
'59 MGA (I6) under construction
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