Fasteddy

I am new to the forum and a novice at sewing. I recently acquired a Singer long arm machine which I hope will be good for sewing heavy canvas and leather. I am having problems with identifying it's model number since the ID plate was removed by the previous owner. Singer Co. has been of no help. All they could tell me was that the machine was made in 1967 based on the serial number which is AR185172. My best guess is that it is either a model l44WSV38 or 144W302 It is a 30" throat long arm and probably the largest long arm they produced aside from special application machines. It is a heavy beast. Does anyone know the difference between the 2 model #'s I listed in terms of features and what they are best used for? Also if anyone knows of a good source(s) for obsolete Singer Industrial machines, I would like their contact info. I would be grateful for any help in identifying it. I will email photos if that would help Ed S. - Nebraska