There's another discussion going on right now I think that's also in the general discussion about GAHH tops and buying one from Autotopdirect.com which apparently is the same product as the GAHH with the difference being price and the warranty you get. Overall I think that looks like our best bet considering $450 for a sewn in or $525 for a whole replacement. They also have options for glass or original.
Here's a link:
http://www.autotopsdirect.com/Porsche-Boxster-Convertible-Tops-s/35.htm
Hope that works
Jake