You can actually fit a gearing that is about equivalent to a modern compact on your existing chainset, if you can find a small enough chainring. Victory and Triomphe preceded compact chainsets by about 20 years. (Good luck - rocking horse poo!)
Just fit another block. You should be able to run about a 25T cog on the existing system. See what www.campyoldy.co.uk
has for sale.
For a triple you'll need a new rear mech aswell. Don't go there unless money is no object.
The new bike might be the best idea though.....
I'm running 50-34 on 12-26 10-speed (or even 13-29 when I go to the Alps) on my carbon bike which has no concessions to retro whatsoever! No retro bike can get near that range of gearing.
Just been doing a bit of research on new chainrings and it appears that the Campag Victory groupset had a BCD of 116mm, apparently quite unusual.
So i've got various options:
1. Buy a Victory triple chainset that's for sale in the US for Â£110!!! But wouldn't I need a new front changer?
2. Replace the existing double chainring for a new one (assuming the BB etc aren't unusual)
3. Go the whole hog and buy a Campag Champ triple chainring and front changer (and bottom bracket?), assuming it's compatible with a six speed sprocket set.
4. Buy a new bike....
Advice gladly received
Completed: 94 Stumpjumper w. M733; ; 92 Dave Yates 731 ; 97 Parkpre Pro-Elite ; Pace RC200 F6 ; Pace RC300; 82 Gios Super Record ; 97-8 De Rosa Giro D´Italia; ; Banani SPX Track bike ; 89 Alan/Mavic Cross Bike ; 05 Focus Cross Team ; 90 Look MI-80 all-Mavic ; 12 Focus Izalco Team/custom build ; 11 Focus Thunder Custom build
Projects : , Brouwer all-Mavic
Stripped : Pace RC303
Gone : GT Karakoram
Stayed in the family: Kuota Kharma, 04 Stumpjumper FSR
Ceased to be : Dynatech MT3, killed by corroded seatstays.