I have that with Dellorto DHLA45M tri jets (perssure tight carbs off a lotus esprit turbo, they are super rare as I have 45mm ones, most of them are 40s. Only US spec turbos got the 45s)
The manifold I have is not the same, it's larger than that one and a one off cast manifold. The one in your pic can be had on ebay for only a couple hundred but you will need to drill it for a map signal if you want a steady speed density system (lines running to all ports), same for idle air if you want to run a remote IAC. Not really feeling the extruded TBs, they look a bit star trek to me.
I also have this, a prototype GM manifold (has casting number /00) if only I could find out what kind of funky injectors go in the bosses that are tig-ed on there. They have a large injector hole, a smaller side hole for some type of common passage..maybe a fuel rail and another one just above what looks like an o ring sealing face, maybe a return. Never could find what it's for.