Search for cibiè "H 160" their original designation to market, should throw up a few option
Think it's correct that in English car fit they were referenced as 5 3/4 inch, for things like triumph stag etc.
If you want period correct equipment, then I guess you want to follow that maker, but there were some good lamps made for Honda accord early models with same fit and "Stanley" manufactured, H4 bulbs and really good performance beam.
