They did come from the factory in 78-81 in 3,4 and 5 speed but they were rare. These guys sell a reproduction setup.
http://www.elcaminomanufacturing.com/ Year One used to sell a repo setup but I don't see it on their site.
There is also a guy on
http://www.Montecarloss.com/ that sell a setup that works with fbody hydraulics. You'll have to poke around to find it. They occasionally show up on ebay so you could check there as well.