So I stumbled across a website of GB products called harvesterbars.com this week because they seem to be the only place I can get replacement GB lo pro nose sprockets in the US. They don't actually carry any lo pro bars except the usual sub-20" ones, but they do carry the full line of GB's ProTop Titanium 3/8" bars. The prices seem about normal in the 20-32" range, $55-75, but they barely go up for the 42 inch bars ($85) which seems like a steal. They have them in Husky D009 mounts in .050 and .063 and in Stihl D025 mount in .063. Best I can tell, the site is run by the GB distributor in the US, Wallingfords, which is based out of Maine, though not 100 percent sure. They've got free shipping and no sales tax.