I did one in one of the mid-century high rises on Riverside Drive which had that kind of wall. Honestly all you need is lots of screws to spread the load over the plaster. Don't put just a few in.

The other thing you could try to do is try to find one of the pieces of angle iron framing the wall (no wood studs, this is an early kind of fireproof construction), but it's not likely to be anywhere near where you need it.