Structural 2011 is available in 64-bit. Are you sure you didn't overlook it?
No. Autodesk is clear that 32-bit versions install on 32-bit Windows and 64-bit installs on 64-bit Windows only. There is no \Program Files (x86)\ compatibility for 32-bit products on 64-bit Windows. You need to download and install the appropriate version.
Structural 2011 is available for 64-bit and compatible with Windows 7. Structural 2010 did have a later 64-bit release available on the Subscription Center.