You coluld try welding it. However, I understand that cast iron does not take welding all that well under the operating conditions of of a downpipe unless you are a knowledgeable welder.
That said, two items you need to know:
1: Hawks Strictly Suzuki is a place to check for downpipes. I go a second generation downpipe from them for $75.00 plus shipping. Junkyards, and Ray's in Iowa are also good choices.
2. There are, at least, two versions of the TracKick exhaust manifold/downpipe. Make sure to check whick one that you have before looking for one. The older one has a three bolt, two pipe junction at the bottom of the exhaust manifold. The newer one has a two-bolt, single pipe connection. If you have the older-style pipe, you may also have a cracked exhaust manifold! If you do (and you are not alone in this!) you'll have a bunch of trouble finding a good used one! It almost becomes a wash costwise when converting to the newer, easier to find manifold/downpipe. The cost of a replacement catcalytic converter and exhaust pipe needed to switch to the new style system is close to the same as a getting a NEW old-style exhaust manifold. The important difference is the fact that the newer exhaust manifold/downpipe are designed to better resist cracking. I'd go with the new system and a new cat. That's what I did on my '93 Sidekick.
I hope this helps!