Economically your best bet is to build the 55. AMT already makes a sedan version of this which is very close to the one pictured. The Revell 29 is available, but is rather Pricey. Due to the Molds being damaged a few years back. It would possibly take another Revell 32 sedan kit to get a flathead engine. The Kit prices alone for a 29 build could easily exceed $70, whereas the 55 could be about $25. add in your paint quality choices, and other add ons like PE, and wheel upgrades, and spot on replica could get up there.