I have tried all of the following applications (download.cnet.com - the free ones), and none of them will convert an RAR archive to a ZIP, without compressing the files ("store" mode). 7-ZIP would be fine, too. [The RAR is a "solid" archive with password (I know it), files "stored" - no compression, used WinRAR 3.5.1]
PeaZip, 7-Zip, FilZip, TugZip, SimplyZipSE, QuickZip, WinShrink.
(A couple of the apps let you try, but the program gives an error - indicating how bad the software is. (Like "unknown header # #.") None of these apps will do the conversion at all.
IZArc 4.1 comes the closest. It will convert an RAR to a ZIP, but it compresses the zip. There is a general preference setting to "store" - but it doesn't effect conversions.
I don't want to extract the RAR files and re-archive them because I need to preserve the modified/created file attributes. IZArc preserves them, but it compresses the files.
WinRAR has the option to convert archives, but I get the error "skipping encryped archive" when I try to convert it. It asks for the password first, and I know it's right because that password opens the archive, and I can read/view all the files in the archive.