This may not help you find seats for your 3, but when I had my '59, back in the day, the seats were as stated above, uncomfortable at best. My seats were in good condition, but uncomfortable, especially on a long trip. (Went to Mexico in the 3 once.) I went to one of those companies (uh, this was before the internet) that custom made quality sheepskin seat covers that fit over the stock seat. These were held on with elastic, as I remember, fit very well and were comfortable as all get out. Made the seats cooler in the summer and warmer in the winter. I used a competition lap belt for a seat belt. I always thought they looked kinda cool in the TR3.