As for the cracks, fiberglass is easy to work with, early cars like this didn't typically have the gelcoat that is common now, so they often have spyder cracks... easily repaired.Reinforcing is pretty straight forward as well, just make sure to sand thoroughly and use some acetone to clean any residue oils/waxes from the surface and it should bond well.
It looks like it was in use on a VW at one time since it has the tubing in the pontoons for the heater/defroster. The use of a separate hood with venting in the front clip also indicates it was likely a later model. There were several other companies that used the mold later on....I don't believe any are still around. They didn't have the wide array of products that Kellison did and the GT40 lines aren't close enough to be able to compete in that market. Although no GT40, I fell in love with them in the 60s while still in High School.
I have 2 and some spare parts(headlight covers included) if needed and also an assembly manual, although that probably will have little use with your intentions.