You may want to try posting a "Want to buy" ad here:
http://www.tractorhouse.com/Default.aspx
Look in the red menu at top left, third item down. Click on it, and go from there. You'll need to register, and give some contact info, and good description of what you are looking for. A part # is really helpful, which you can proabaly get at AGCO PartsBook site.
Or, here is a list from the same site, of dismantled 175's in salvage yards :
http://www.tractorhouse.com/list/di...=3&Manu=MASSEY-FERGUSON&Mdltxt=175&mdlx=exact Might be easier to have them call you, instead of going through that whole list. Some have a description of the type transmission, but most don't.
They usually contact you within 36-48 hours. I've had 100% success rate posting on there looking for N/A parts. One particular item was a hydraulic pump gear for my MF 180. Give it a couple days for all that may have one to contact you. Pricing, and shipping can vary, depending on location.
The multi-power transmission on my MF 175 is not working very good and needs to be rebuilt. Estimates are from $2500-3000 by a dealer to do the job. Does anyone have a good 8 speed or 6 speed not multipower transmission and housing for sale? SN for my tractor is 163925.