sounds to me that you have those 195/70R14 tyres commonly fitted back then?
These are of the 'reinforced' type construction and do indeed have a universal 42psi maximum working pressure, this for the above size depending on load index number, 95 or 96, is, either 1420kg or 1380kg
Today being scarce so fairly expensive, these tyres are in general replaced with a choice of 'Commercial' type tyres, ie, the three options are 175R14C 99Li, 185/75R14C or 175/75R14C both with a 102 load index
Of different construction, these can and do have a higher pressure requirement.