Personally I use LiFePo4 batteries for all my home radio equipment, both receivers and transceivers. A 3 cell LiFePo4 will provide 9.75 volts, well within the specs of the above radio. A 4 cell runs my FT-891 with 13.2 volts. The 4 cell batteries are 8.2 AH and I run 4 in parallel. This provides almost 8 hours of SSB operation at 100 watt output. Of course, that much capacity wouldn't be needed with just a receiver. The main benefit of the batteries is that they are a 100% clean power source, no RFI. With the proper charger they last a long time as well. All that would be needed would be the power plug itself and some wire to make up the cord. I'm sure an adequate system could be set up for a receiver for the same or even less money than the above switching supply.
Just a suggestion.