Continuing my search...
http://cgi.ebay.com/ebaymotors/PORSCHE-BOXSTER-2-5L-97-99-STAINLESS-HEADER-HEADERS_W0QQcmdZViewItemQQhashZitem300145605387QQi temZ300145605387 those caught my eye. Cheap, no buy it now, etc... You think they are the same as every other ebay header? They look like it.
And back to my original question, can 911 headers have the gasket cut off and welded on backwards and fit correctly for the boxster?