The Boeing 2707-300 was illustrated by various artists for Boeing. At least 4 different styles can be found online. The two styles above were verytraditional beautifully painted but the two variants here are more styalised.
Somewhere there must be full sets of the artists impressions for all 26 option holders. Sadly only a few have made it online. But every now and again new ones get posted. The earlier versions of the Boeing SST were usually only shown by Boeing in House Colours. Individual airlines had their own artwork done, and these also appear online.