I haven't modeled the springs yet. I'll add them to the set soonish, then make the STL files available.
STEP 214 Format: http://captainslug.com/nerf/Crossbow95.zip (2.6mb)
The internal parts are 100% measurement accurate. The shell however isn't exactly dimensionally perfect. It's been altered for improved strength and more compatibility with 3D printing (hopefully).