Something of a long shot, but someone somewhere might have one. They
do not appear to be available from the usual UK sources. [I bought the
AR146 without the CTCSS module quite a few years ago, before CTSCC
became popular in the UK for repeaters. Due to changing circumstances
it was confined to the attic, from where it's been re-discovered and
I'd like to get it back into service.]

Alternatively, if someone knows the radio well enough, can anyone tell
me the connector type used in the radio into which the CTCSS module is
plugged? if I can get the 'other half' I can probably find an
alternative CTCSS module to use.

TIA