I have no idea on value. Around here I would not even know where to look for a 1955 anymore let alone where one has sold. We used to take care of 400 + Olivers. There may not be more than 40-50 around here that people use to farm with. We also sold more 1950T tractors than the 1955 models. Also there probably  10 1750/55 and 1850/55 tractors here for each 1955 tractors