Hi Mike,
Whilst I have no experience of bushes on SA 131s I recently purchased SuperFlex trailing arm bushes for my 1978 Series 1 which were actually listed for the 124. It would seem to me that neither SuperFlex nor their manufacturer really knows which car they fit
I also had to fit SuperFlex Ford Escort mk 1 bushes (albeit slightly 'modified' with a Stanley blade!
) to the anti-roll bar on my 131 Abarth, so in my experience it has always been better to do a little research around the SuperFlex 'range' before taking the word of their catalogue.