Wings magazine did a story on the Regulus in their Dec, 2002 issue. It mentions that in the 50's Revell issued a kit in a fit the box scale. I don't know if you would be able to locate one but the article said the original cost was seventy-nine cents but now worth $150.00. A lot of parts were taken "off the shelf" so it might be possible to scratchbuild one.
Berny
Phormer Phantom Phixer 
On the bench
TF-102A Delta Dagger, 32nd FIS, 54-1370, 1/48 scale. Monogram Pro Modeler with C&H conversion.
Revell F-4E Phantom II 33rd TFW, 58th TFS, 69-260, 1/32 scale.
Tamiya F-4D Phantom II, 13th TFS, 66-8711, 1/32 scale. F-4 Phantom Group Build.