Hi Juvela, the rear wheel is indeed a steel superchromix and is in storage already. The front wheel was alloy, I forget the rim make but the hub is Super Olympic so it was probably original. Yes the brakes are also Super Olympic and not very good quality so I changed them out already. According to Disraeli Gears 1973 was the first year for the V-luxe RD and the Comp-V 6 hole FD ran from 1974 to 1979 so yes somewhere mid to late '70's.
I'll check out the seat post diameter later Tom but shorn of it's steel pedals, seatpost, rack etc the weight has dropped dramatically. It's currently sitting at just over 22lbs minus seatpost and saddle. I'll post pictures when it's all done.