thingiverse has one for wood. [
www.thingiverse.com]
here is one dxf file with support for heated bed.[
www.thingiverse.com]
hope these help. seems like someone needs to add dxf files direct link to download wiki page for prusa. I'm sure it is the build files though.
only thing i see specific is size of bed.
140mm×225mm print bottom plate (not used in recent iteration 2 designs)
225mm×225mm print top plate