JA - 29 is listed in one of the resources as having been made by Brother. I wouldn't be surprised that it was all metal, with few if any plastic parts. Likely will last a few more generations if kept oiled and cleaned.
Yes, it would have fit into a cabinet or sewing table. Very likely it can also be put into a standard carry case. Lots of choices available for carry cases including some with a base that the machine sits in.