3 port vacuum TCS replacement part number?

[C10wip]

Hi all,

Just recently joined, thanks to all for the excellent info on the site. I bought a 1980 C10 Custom Deluxe for $1500 so as you can imagine, it needs some work. It's a 250 ci with the three speed manual. I have already done the Jeep steering shaft mod, nice improvement.
So my question today - On the vacuum circuitry for the air intake preheat - it looks like one of the vacuum valve TVS's outlets got broken off at some point, and the PO routed the vacuum directly to what looks like a choke plate vacuum actuator. The TVS now just has two hoses and one goes to a golf tee, so it's not doing anything. I am having problems finding the replacement TVS - Rock Auto doesn't seem to show one, and AutoZone shows multiple three port vacuum switches which are apparently coded. The one I have has a black plastic body, but I'm not sure what that means.
A picture of the whole deal is attached.
So - can anyone shed some light one which part this should be?

Thanks!