I paid $75 for my 1902 model 27 with sphinx decals. The cabinet is in decent shape and it came with attachments, although they are the standard low shank attachments that are readily available. Your biggest challenge might be in locating bobbins and/or shuttle that fit your machine. I believe the 127 still used the "bullet" type shuttle, with long skinny bobbins, and those are not so plentiful.
The belt isn't a problem, those are readily available too. Personally, I think for the condition you have described, $50 would be a more reasonable offer.