The Boeing Company (NYSE:BA) has proposed funding its acquisition of partsmaker Spirit AeroSystems Holdings, Inc. (NYSE:SPR) with stock rather than cash, according to people familiar with the matter, a last-minute twist in deal talks that comes as the jet maker burns through more than $1 billion a month. Boeing and Spirit, a jet fuselage maker it split off two decades ago, were closing in on an all-cash deal this weekend when Boeing switched to an offer consisting largely of company stock.