I don't believe that saddle is original.
To me, that bike is in serviceable condition, but there is more rust than I would really like to see. When I see rust, it makes me think the bike should really have a full teardown and refurbishment with new grease & bearings, etc. Because of the condition, this is not going to attract collectors. I would just get rid of the old tires and advertise it with new ones. The average buyer will value that more than originality. You can keep the old ones and ask them if they want them.
Value depends a lot on where you live. Here in NYC I could probably get $150 for it, if it had rideable tires.
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1964 JRJ (Bob Jackson), 1973 Wes Mason, 1974 Raleigh Gran Sport, 1986 Schwinn High Sierra, 2000ish Colian (Colin Laing), 2011 Dick Chafe, 2013 Velo Orange Pass Hunter