Don't really know the material costs as I've had most of the materials a while.
The reel seat hardware is about $17, the wood I've had in stock for a while. I got a good deal on some stuff off ebay and bought a bunch. Cork cost is probably in the $30-$40 range.
The only other materials to factor in are Rod Bond for gluing up the rings and seat and the thick CA for the finish on the wood.
FYI
I have about $200 in materials in this handle.