When you say timing cover you talk about valve covers (2) or the front cover on the belt side (1) ? I found gasket for valve covers recently. You make a search on e-bay and company specialized in buying old new parts from Ford dealerships but when I called at Ford they said they still have some for each side (at least here in Canada, probably at Toronto for 60$ can.). I don't know the situation for the front cover gasket. If you're doing valve covers gasket, I suggest you to replace the seals of the plug well. Mines begun to leaking on the plugs when I remove valve cover... (Ford still have them too for maybe less than 10$ each and they are a bit harder to find on the net.)
You can find an old a/c compressor on e-bay around 225-300 $ If you have the Ford part number, google it and you can find some others place to buy it. I never saw separate parts for it on the net.
Good luck,