I'm not building any yet, but if I was going to, I can see several options :
1. model them in Solidworks or Rhino and print them out on a 3D printer and v-Bag on carbon and glass. I would model them smaller with compensation for laminate thickness. The 3d prints could even be made in top and bottom halves and filled with carbon resin and glued together, then laminate outside. Might be difficult to keep overall shape totally symmetrical. 3D prints warp and some change shape with humidity. With some simple jigs it might work.
2. Model like above, but mill out of cibatool high density foam or wood and then vbag on laminate. You could even make a wood and carbon " plywood " and mill that, creating custom core that has some stiffness, spring and more stability in core.
3. Low tech way is to model it in CAD and print out paper templates and Shape it by hand in cibatool or softer wood/plywood . And vbag laminated.