Mk6 1995 Diagnostics

Hello All,
I have a  1995 Mk6 GT2.0.
Have just had a bit of an MOT disaster on the CO emissions.
It usually gets flagged up and my mechanic gets it through by using an additive and warming the engine up before retest.
But this time that hasn’t helped.
He said we will need a diagnostic tool for this model car and none of his will work on a car of this age.
My questions are:
    1.    Is it still possible to buy one of these somewhere? 
    2.    If not, is it possible to buy something similar + an adaptor that will fit the port.
    3.    Google tells me it is an OBD 1 port - so could an adaptor for this be used on a newer tool if I can get one?
    4.    My mechanic suggested trying to find someone local who owns one, but not sure how to go about that. I’m in South West London, so I guess there could be someone near here.
Bit worried - if I can’t find a tool that will help mechanic diagnose the problem - could be the end of my lovely car. :(
Grateful for any advice please.
Many thanks,
Jon

sounds like it needs a new CAT

you can always do a flash test, link 2 pins, turn the ignition on

Great, thanks for the help Flash!