WE 566 wanted

[rcourtney]

These key phones 566FB 566MB or 566MD were exclusive to the 755A PBX.
A crossbar system that was a 4 line key system with an intercom on steroids.

Advanced for back then, my father had one at his office in the late 50's thru early 70's.
6 round clear buttons and a non-curled handset cord.
While the sets were available in colors, the extra rental cost made everyone get black.

I don't have a 755A PBX but but would love to dream about my father's office with a set like his sitting on my desk.

[5415551212]

Here is a 564HD, the look is close:

https://www.ebay.com/itm/267270498128

[5415551212]

I happen to also be curious about these 755 PBX's (I started a thread here) and stumbled on this phone on ebay, and it seems its for a 755 but not the vintage your looking for;
https://www.ebay.com/itm/357686781707
Its got non-illuminated buttons.
Since your good at PCB design you could make a line card to control one of these phones reading inputs from the buttons, you could build off Howard Harte's work here: https://github.com/hharte/we755a_slc you'd just need to adapt that to emulate the 755.
If you have a shoebox 1A2 system you could even make it a hybrid line-card and put one of these phones  on a 1A2 system, as the shoboxe systems and their power plants are still somewhat easy to find.

[RDPipes]

I happen to also be curious about these 755 PBX's (I started a thread here) and stumbled on this phone on ebay, and it seems its for a 755 but not the vintage your looking for;
https://www.ebay.com/itm/357686781707
Its got non-illuminated buttons.
Since your good at PCB design you could make a line card to control one of these phones reading inputs from the buttons, you could build off Howard Harte's work here: https://github.com/hharte/we755a_slc you'd just need to adapt that to emulate the 755.
If you have a shoebox 1A2 system you could even make it a hybrid line-card and put one of these phones  on a 1A2 system, as the shoboxe systems and their power plants are still somewhat easy to find.

I'd be suspicious of this phones capability of being used for it's intended purpose as the buttons look to be plugs.
I have 6 or more of these type 400 phones in my collection and you be hard pressed and impossible to get all the buttons pressed in at the same time as these photos show.

[rcourtney]

A lot of cool information.   My father had a 755A at his place of work.  The 566 phone was on his desk,
which if I were to find one, use it in place of a single line 500/2500.

I don't own a 755A, currently on VoIP.

He had a Dataphone 113A (Gray color) when he worked from home.

All for nostalgic reasons.