While I'm hardly an expert on this topic, it seems to me you are looking for options to deal with a less than ideal situation. Compromises might well be needed. I attempted to provide a multi-outlet solution for consideration. The H-10 is inexpensive. See how things sound powered up in various ways. I'd recommend plugging your amp directly into one of the wall receptacles Run the H-10 off the 2nd receptacle. Plug your other audio components into the H-10, directly. Run a power strip out of the H-10 for your low current- draw, non-audio components.
Other solutions are possible - like hiring an electrician to run new power cable from your fuse box to newly installed receptacles.
Other solutions are possible - like hiring an electrician to run new power cable from your fuse box to newly installed receptacles.