Think thats a 93 model, 653 tubing with shimano 600 ultegra i believe. Nice bike, always wanted one of those! Not sure about cost, but it wouldnt have been cheap - circe £6-700? (maybe more) Someone else with more knowledge might be along shortly....
From recollections of Dawes brochures of the time this was the top-end model (they never did 753, wonder if they had trouble getting approval?). Don't recall the STI-fitted example already posted although it obviously did exist. An earlier model (ca.1991?) had, from memory, a lilac & green paint job, before that I think the colour scheme was mostly white with pink and yellow flashes. All variants used an Ultegra group and a 653 frame.
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