It's highly unlikely there will ever be a JB for 4.3.5 on iPad2, and iPad1 owners must put up with a tethered JB...
You only get SHSH's which Apple are providing, which is currently 4.3.5. They have nothing to do with anything else, such as the version you have installed. You can't save 4.3.1 now unless you have an iPad1 and use iFaith. See our SHSH FAQ sticky for details.