Late 60s Luxman SQ77T/II weird speaker outputs?

[teast]

Hello everyone,
I'm planning on buying a late 60s solid state Luxman SQ77T/II amplifier but I couldn't help but notice these odd speaker output connectors. Has anyone ever come across these and would know of an adapter to use normal speaker cable with them? Many thanks. Photo attached:

 

[Dswankey]

I've attached a picture (from the web) of an example of what it should look like.

I've also paged @Blue Shadow one of AK's resident Luxman guru's who should be able to point you in the right direction.

 

[Blue Shadow]

It appears the adapter needed is a philips head screwdriver to remove the sockets and install a connection that is something the owner would like to use.

Finding something called a loudspeaker strapping cord would require knowledge of the Japanese language and ability to search their auction sites and vintage audio parts providers as those units sold more there and anywhere else in the world.