Bonex / BEC Distribution maybe still around. Or J.A.B. Electronics
These were the main UK Stockists of Toko coils etc. after the demise of Cirkit & Mainline Electronics concentrated on their takeover of Greenweld / resurrection of Jackson Bros.
However I think all these Toko coils are now obsolete, as they are now classed as 'old' technology.
You may well also find that custom parts were used in these CB's, although there may be similar ones in their 'standard' ranges
Note: It is actually a (resonant) IF Transformer, rather than just a variable, from looking at schematic. So need something with the same turns ratio, as well as being designed to be resonant with the same external capacitors.
CB Parts suppliers like SJ Tonks, Knights, Nevada, Truck King etc. used to be able to supply many of the more specialised parts, but not sure how many are still around - Knights are:
https://www.kcb.co.uk/ and maybe Truck King).
Otherwise, if it was used on other Cybernet chassis, then might be able to obtain from a scrap unit - There were so many wrecked CB's back in the 80's that most people repairing these had their own graveyard boxes of these to salvage parts from.
A copy of the Cybernet Export Manual may be helpful.
http://www.radiomanual.info/schemi/V...ew_version.pdf
http://www.radiomanual.info/schemi/V...ld_version.pdf
And a manual with fuller technical details on the PCM001S (But only says SSB Detector for T7 - no actual part number):
https://www.manualslib.com/download/...Star-2200.html
But maybe a SAMS FotoFacts manual from CB City in USA etc. is probably the most detailed, having many pictures and maybe parts lists:
http://cbcintl.com/docs/sams.pdf