That 67 setup I sold several months ago had that wedge shaped one, also the other support you now need. I know one or two of the mounting brackets for the 67 were C7 numbers but a good majority was what would have worked for your later 66, so it seems, so keep that in mind on your hunt, that is to NOT exclude looking at some 67 parts since several are the same.
Also, FWIW, when I did an Assembly Manual Study on those 67 parts to properly understand what all it would fit, it seems that the pulley differs from OTHER potential options on the car and how the setup was shimmed on the mounting brackets (read as move a spacer here or there to move the pump forward or backwards on specific applications e.g. with power steering or without, or with air conditioning or without or any such mix of options)
It was a little confusing but it WAS POSSIBLE to sort out what engineering number an nstaller would use on the pump pulley but you really needed to study the assembly manual's notes. I imagine it isn't much different for the 66 system you are trying to build. I hope you have ordered yourself that Assembly Manual by now. It WILL really help you out A LOT!