MUCH easier to find some thick and fluffy luxury bath towels to put on the orig seats. Then you can slide better to get in and out of the car. I do that on my leather interior vehicles. MUCH less expensive, too.
For the seat backs, make a drape and sew one side so that it all slides over the back and one side retains it in place.
In general, very few OEM cloth and vinyl bucket seats, except in some GM cars. Ford "invented" woven vinyl for bucket seat inserts in the later 1960s or so.
There are ALSO many velours which look nice, but are really thin in "gauge" and backing material. As is the difference in the '77+ Chevy Caprice velour and the fabrics used in the similar '77+ Pontiac Bonneville. The Pontiac-spec fabric is twice as thick and wears like iron. For little more additional cost/yard. The velours which Chrysler started to us in the 1974 "Formals" were thicker than that, with a deeper "nap" in the fabric, more fitting of a more expensive vehicle.
Remember, too, that velour can also become damp from the occupant sitting on them, too. Which can make the brocade fabrics Chrysler used a better possibility.
ONE other things about the pre-'74 Chrysler trim codes. The huge bulk of them had a pearl coating on them, including white and black. That gives them a bit of sparkle in the sun. Until you put another OEM similar color fabric/vinyl next to them, you normally don't notice this, but it's there. A trim shop guy showed me this and I was shocked at how much difference it made.
The downside is that on the white vinyl buckets in my '67 Newport, as the pearl ages, it can lend a dingy look to the vinyl that won't wash off. But even then, it looks better than a similar GM white vinyl. To me, this is one reason the interiors in the Formals don't have quite the "pop" that earlier interiors of the same color did.
I discovered these things when I was looking for a newer OEM fabric for our '66 Newport Town Sedan, with is the brown color interior, cloth and vinyl. By comparison, the OEM '74 brown velour looked like "mud". This was in about 1975.
Just some thoughts and experiences,
CBODY67