I think that your Helicomatic hub would be fine. But... you are talking about October. Ride the hey out of it in July and August and if everything looks pretty shady in September, get a hub and a different 6 or 7 (you cannot do 8 or more - got to spread the frame) freewheel. Your rig is friction, so pretty much everything will work. I rode a bit with helicomatics back in the day and I could really not tell much difference... all I have now is the adjusting tools (a couple of them) that are relegated to beer bottle openning duty these days . No matter what you do, stay away from that foil Felt