Here's is a near new Triumph OEM Accessory passenger pillion seat to fit 2014-2016 Thunderbird LT models. I've read this seat is about 1" wider and longer than the stock LT passenger seat and a bit thicker, plus made with better materials. Should be much improved comfort for your passenger.
Excellent shape, I see no wear or damage. It is lightly used however so shows some very light marks from normal use, none that stood out to my eye.
Note: This is made for the LT models, but, I've read where it will also fit with the stock front seat on the regular Thunderbird 1600 1700s. I have not seen this, just read about it. Mounting points look the same, see last pics for reference only comparing to stock regular 1600 passenger seat.
Triumph Accessory part number T2302347 retailed for $507.03 according to internet and I'm unsure if this seat is still available from Triumph.
Buyer pays 48 state shipping of $25, happy to sell internationally only via ebay global shipping program, thanks!!!