One thing you might want to consider is to hunt for either a MIJ or MIA 75 re issue, I just picked one up used and it nails that 70's bark to the T!
You can get them a lot cheaper an MIJ should go for 550 to 650 and a MIA, 800 to 1000. Like all Fenders there a crap-shoot, you'll play a lot before you hit "the one" but thats true of the 70's too. Fender wasn't known for great craftsmanship in that era, and there's a lot of real mediocre stuff out there under the "vintage 70's" category. My fear with the "vintage 70's" is that when you start getting up around 1700-2500 there are an awful lot of far better put together basses that can get that vibe. Sadowsky Metros, Lakland Daryl Jones 1000-1300 NEW!, and some of the Fender custom shop stuff (which is far better put together then most of the 70's stuff IMO). Unless your a collector, or getting a great deal, Just food for thought, not to hijack the thread or anything!