It depends on the restoration done. Some total fridge restorations include the refrigeration system which might be more efficient but in most cases the simple design of refrigerators back then didn't use close to as much power what modern frost-free fridges do. In many cases the "restoration" just includes cosmetic fixes and not 'upgrades' to the appliance itself
There would usually be minimal difference in gas usage of a range although older gas models likely have a standing pilot that burns all the time. That uses minimal amounts of gas and likely wouldn't be noticeable.
BTW. There are also some 'retro look' appliances that might give the idea of age without actually being old.
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Dan O.