I'd stick the cool little Pug mixte around 1972-4. The gutrippers argue a bit later, I think, but the decals are in that period. And I think the gutrippers may be a later "upgrade", as may be the bars and brake levers, and seat, while I'm at it. UO18, I think, if memory serves me correct (I always get confused with the regular/mixtie/touring designations, it could be a UE8). Whatever, Mixte version of the UO8.