Could you fit one of them old skool brake boosters like wot Magura used to fit on their cantis? Iirc there's a slot at the top you could fix yr stop. Might be too deep though
I think I probably wouldn’t like the look of it.
My latest thought is wether a cable stop like this would work (with a mock-up using a band on front mech mount) The cable would be pulled round a pretty sharp radius, though. Which may or may not be a problem - it might eventually fray perhaps.
Could you fit one of them old skool brake boosters like wot Magura used to fit on their cantis? Iirc there's a slot at the top you could fix yr stop. Might be too deep though