First of all, do you want to go with a contact point distributor or an electronic? I like shopping Summit Racing for things like this, they are about the best price, large selection, good brand names and shipping is really quick.
I have narrowed it down to like 74 distributors, http://www.summitracing.com/search/year/1969/make/ford/model/mustang/part-type/distributors/engine-size/5-8l-351/computer-controlled-compatible/no?SortBy=None&SortOrder=Ascending&keyword=distributor now, you just have to choose what other options you want.
They should have the pulleys also. What accessories will you be driving? I assume there is no A.I.R. pump. Is it power steering or ac?
So, you would have the water pump, alternator and crankshaft pulley, anything else?