With regard to the Space 1999 Eagle, in theory I think you could clone with one of the MPC models. They are much more detailed than a blow mold, of course, and you have work out how the aft end (engines) can be modified to receive a body tube. I have not worked this out but it shouldn't be too hard. Some of those models are quite close in scale to the Century nose cone. I have in my possession both the Centuri starter kit ($$) and a couple of MPC kits (pretty reasonable $). Note that a few months ago the Centuri kit that kept being relisted on ebay was part of a Martin Landau estate collection.