I'm 181cm with the same inseam and ride 60cm Surly Pacer with 59cm top tube and 9cm stem. My first bike was a 56 cm Cannondale R400 road & I still remember how extremely uncomfortable it was (I got it for cheap too by the way). The problem with smaller bikes is that you'll have a very large drop between the seat and handlebars whereas they should be about even for touring bikes like LHT. That's why it is advisable to get a touring bike one or two sizes larger than your road bike (I ride 58cm Merlin road with 10cm stem and 2" saddle to handlebar drop). The general rule for the bikes with horizontal top tubes is to get the largest one you can clear & then get a stem that fits. If I were in your shoes, I would get a 60cm LHT with a short stem. A good resource for touring frames sizing is this:
http://www.rivbike.com/article/bike_...g_a_frame_size

Hope it helps...