Here is a link to a good inflation calculator:
http://www.westegg.com/inflation/
The 1908 Sears price is $520.62 in 2006 dollars, still not a bad price.
The comparisons from Vince's list:
S/42, 1920 Commercial @ $165: $793.47
Krieghoff @ $250: $1,202.23
1902 AE @ $500: $2,404.45
1914 Navy @ $350: $1,683.12
LP-08 @ $200: $961.78
--Dwight