you should be able to replace the power steering pulley easily check with ohiomustang, hemikiller, and if you get desperate i have a few more contacts you can try.
right now there are a few on ebay as well. just match the part # on your old one.
as other mentioned there is a special tool that both removes the pulley and installs one. the center shaft of the power steering unit is threaded and the tool attaches to it allowing very easy removal and installation of the power steering pulley and also the alternator pulley. the remover is 4 piece you insert a threaded rod into the center shaft then a 2 piece collar locks around the pulley nose, and a locking ring goes around it that has a nut on it, you hold the nutted end of the threaded rod with a racket and as you turn the nut on the pulley nose with a open ended wrench the pulley is forced off.
to install there is another similar tool that pushes the pulley onto the shaft and keeps you front pushing it on too far.
the tool is kind of expensive and i remember it was hard to get as well, had to be backordered to get one. there are these cheap pullers I've seen for 20-40$ they are total junk and don't work with the ford pulley.
I can't remember where i bought mine maybe from OTC. I'll have to take a look. i think the tool costs 150-200$
It is a good excuse to buy the tool if you like tools.