Hey Mike welcome to the board from a Wolfe City native.
I shopped for one a couple years ago, at O'Reilly and Advance (didn't bother with AZ b/c this required the parts guy to do something that was not routine). I asked for one for my application and they gave me a price around $180. So knowing that pretty much any q-jet would do the trick, I asked the parts guy to show some prices for other q-jets for other years on 350s. He somehow came up with a list of all the q-jets that might work and I picked the cheapest one (~$120). And it's still going.
I just looked for the cheapest one with the right choke config., enough vacuum ports, and a power brake fitting in the back (if you even need that.) Oh, and don't expect two rebuilt q-jets with the same model number to look the same. They will take completely different carb "frames" (?) and as long as they jetted them the same, they'll call them the same model. Good luck.