Get a Tubus Logo rack, and mount your bags on the lower rail which extends back further. Looking at the wee picture above, you might be better off fixing the rack to two P-clips attaches to the seatstays, rather than the braze-ons. I think whatever you buy, if you're determined to use that brake-booster thing, you'll have to do some crazy kung-fu DIY to make the rack fit.
Why the brake booster? If (no offence intended here, just an observation about shoe size!) you're a large and possibly heavy chap and need a little extra in the braking department, you could try hydraulic rim brakes instead of centre-pulls?