I don't know if the X10 stuff is still manufactured but Radio Shack and some mail order catalog that I can't remember the name of, (maybe BSR?) used to sell it in the US about 30 years ago and I still find a lot of it around garage sales. Oh and Levitron or Leviton (not sure of the spelling) also used to sell it. Most of the Radio Shack stuff was absolute crap and nearly all it failed within the first few days.
I still have a few pieces installed and those have been working for over 30 years at this point.
I would suggest looking for pieces of it on E-bay but I won't waste my money of any of it that's marked Radio Shack. I don't know how common it was in your country but in the US, I would look for it in thrift stores, hamfests, garage sales and the like. And if you have a local sales paper like Craigslist, you might put a want ad in it.