1989-95.5 models were simply "pickups" in the U.S. (or as a autostore system might list, "truck (not including t100 or tundra)". so a like trimmed truck bucket from one year, should be close to a similar year bucket seat in dimensions.
Tacoma, did not exist until 1995.5 model year (Later model year switch over).
And as far as a Tacoma Bucket (or bench), never had one, so could not give a definitive on that.
May be able to ask someone on the Tacoma Section, about seat dimensions, but probably better just sticking with something that fits your generations seats.
Lots of good info on this site and the search function works great... not like some others I have been on.
As for your question/s.. rivethed hit them spot on..... and gave me a craving for a lemon donut at the same time! ha