I don't know if this helps but i just ordered these for my car. At 299.00 each with free shipping i thought it was a good price and they will fit just right. After the research on here i could see the need for headrest. These headrest are removable so you can take them out when you get there. May not fit your application and i understand wanting them not to stick up above the rear deck but because of head to roll bar issues i chose to go with these. Just my 2 cents.
http://www.racing-seats-usa.com/20051.html
These are nice too.
http://www.cobraseats.com/classic_cs.htm