Well, that didn't take long. Basic units like a FiTech for the base "head unit" and wiring stuff will run you about $950 taxed/delivered. You'll still need a fuel system to feed it. Best place for that is Tanksinc.com. An EFI ready tank is just under $300 plus you'll need a pump, fuel sender unit, filter, lots of fittings and hose/line. EFI requires a return so twice the fuel lines. You're looking at almost $600 there without the hose/lines and fittings. I'd figure a couple hundred there minimum. So call the full fuel system $850 to be safe. That puts the complete swap at a parts cost of about $1800.
The work to install is pretty easy. Hardest part will be the fuel lines. Without a lift you'll be spending a fair amount of time on your back. Wiring is fairly straight forward. Just need a hole or two put into the firewall and a few simple connections for power. You could use the clamp style connection for the O2 sensor but I will REALLY recommend welding a bung in. If you can't do that a muffler shop could do it easy enough. Figure they hit you for a few dollars there. Have that done before the install and just put a plug in it until the install.
If you're like me I'd set aside a couple hundred for unforeseen or desired "extras" for the process. Maybe a new air cleaner, for example. Nicer braided hose or fancier fittings. It's easy to run up the tab!
DO NOT DO ONE OF THOSE FUEL CANISTER UNDER THE HOOD THINGS. Never heard anything good about them. Put in a tank and in-tank pump out back and do it once, RIGHT, and never look back.
I still am a big fan of the FiTech system in my mustang. I even considered doing the blown flathead with EFI but I wanted the look of the old Strombergs and the only available bolt on stuff was questionable and $$$. I'm thinking vintage blown hemi for the model A and it will be EFI for sure.