I was looking around the net and found these Weber 13B intake manifolds. I am new to the whole rotary engine thing, so I do not know if they are useful. But these things look a lot lighter than the stock intake manifold on Tracy's website and easer to work with than the Paul's cast manifolds.  

The manifolds are halfway down the page.

http://www.tweakit.net/shop/advanced_search_result.php?keywords=13b

Alex