yes thats prob what i i would replace them with. i have a spare set. allthogh it still involves removing the old mafac brake posts (mounted above the rim for the centrepull pivots) and brazing on a set of standard canti posts. cant see a way i could mount the hs33 with the weird brake post positioning designed for the centrepulls.
what im really looking for is a way to get good braking power without shelling out for Paul racers or having mess with the frame and have all the faff of repainting. thats why i started looking at bmx and mtb u brakes but i cant find any info on compatibility