Nowadays, with genuine socket boxes in short supply, people are using their own ingenuity to make socket outlets for their own Econet installations. I have seen various home-made forms of socket box. The circuitry inside a socket box is very straightforward and so it needn't be difficult to put something together which will work reliably as long as the Econet specification is followed.
Apart from this, there are at least two other official forms of Econet socket outlet in existence.
When Econet was first introduced back in 1981, it pre-dated the socket box and so connections for Econet stations had to be made directly onto the network cable. This was done either by soldering 5-pin DIN sockets directly onto the network cable at required points along the wire, or by using DIN sockets mounted in facia panels in a similar fashion.
This arrangement was not very reliable as there was little in the way of strain relief as a result of the way the sockets were connected to the main network cable, and were prone to breaking.
The second form were Digital Services Solderless Crimp Outlets which were similar to direct connection of sockets onto the network cable, except that a special locking connector was introduced between the cable and the socket to eliminate the strain problem.
I have been able to find very little information about these solderless crimp outlets. If you have any information, then please get in touch with me here.
More recently, there has been a new type of socket box made, combining DIN sockets and Ethernet-type RJ45 sockets. A limited number of these - as boards only, without any boxes - were made a few years ago. I did get a handful of these at the time; I'll put the pictures in this section as soon as I get round to it.