Its a 840 RO (write only) vs a KSR which would have a keyboard making it a hard copy terminal. Used where you needed a hard copy terminal... Chemical plants, telephone systems. This is just a serial printer version.
"CRM"on the box means Customer Returned Material which means it was purchased and returned or it came off a lease. Date marked on the box looks like maybe 2010 so the ribbon maybe dry and not print. It won't go into TEST mode without paper in it. It should print a barber pole. Under that little door is a test button along with buttons to set margins, paper length and to configure the serial i/f.
It had a optional parallel i/f but you had to remove a piece of the case. There are some square slots for telephone RJ12s but they probably don't have connectors in them since this version is only a printer, no modem.
All that decayed foam was for noise reduction. I would just blow it out with air or a vacuum. Probably works fine if it powers on. TI over engineered everything and they were built like tanks with metal. (Unlike HP)
TI's TPD Division Temple TX (terminals/printers) was sold to Genicom in 1992 when the Computer Div Austin was sold to HP. Not sure if Genicom kept the 840 going. The 99/4a (most of this site is concerned with) was Consumer Products Div outta Lubbock. (calculators, watches, speak n spell etc). Not sure what happened to them. TI sold the Defense Group Dallas to Raython and Geophysical group Dallas to Halliburton. Pretty much returning to be a Semiconductor company.
I was with the Digital Systems Service Div outta Houston for 13 years.
Most of the TI repair co in Houston are outta business. Preferred Computer Service (my company), CalTex Computers, Omni Data, Linco, BBS.
You might try Data Refects Computers, used to be off Tidwell, I think they are on Brittmoore now. Bill Leach 713-937-0099.
You can try Lake Erie Systems (Erie PA) www.fastprinters.com or Trident Computer (Troy MI) www.tridentcomputer.com.
If you are trying to find a local user, your best shot would be old Farm Implement dealerships (John Deere & National Farm and Power Equipment Dealer Assoc) or a Ford Dealer as they were all big customers. Also Churches and Boy Scouts of America had TI UNIX and Xenix systems. It was HP's intent to swap those for 486/586 servers and both Ford and NFPEDA computer s/w support moved to a west coast VAR that sold IBM Netfinity. I think they were eventually bought by UCS who was bought by Reynolds and Reynolds.