Buildling a 2.3 shouldn't cost all that much more than a 2.0. You don't need different rods, you still use the everyday off the shelf rods you'd use in a 2.0 build. What you need is the stroker pistons, which typically are the same price as the 2.0. They just raise the wrist pin location on the piston. The only real added cost is the 2.4 crank you have to purchase (which it sounds like you already have one), and possibly some material removal on the inside of the block.
Link to pistons that you could use.
http://www.maperformance.com/store/home.php?cat=1437
You'll see the stroker pistons and the standard 2.0 pistons are the same price. Looks like Wiseco and Ross also makes some for the same price as their off the shelf 2.0 ones.
I was considering a 2.3 build awhile back, but got scared off a bit when I was finding out that the 2.4 cranks weren't all created equal. Some people found there's were hardened, and others found theirs weren't. When I found a company that sold used cranks, they said they could not verify whether or not they were hardened, so I ended up just staying 2.0.