So you could get a double derringer for $8.00? Is that a week's pay, a month's pay for the average Joe back then?
I believe that there was a lengthy depression in the latter part of the 19th Century. If I remember correctly, in the 1890s, wages for what we'd now call blue-collar workers were running about $1.70 a day. Some trades in the big cities made close to $4 a day. Women working in the textile industries were paid under a dollar a day.
Lots more data here