This is not a matched set by any means. The 6" is a 1924-1953 generation 3. The 8" offset No 81 is from 1924-1940 and nothing special. The 10" 72 is also a very ordinary tool from the same period. The 0973 is actually mildly interesting. Its from 1969-1983 and is a generation 4 model. You can tell by the tapered shaft. There were 4 varieties: The earlier ones from 1954-1968 were 973 and 673 (RH and LH) and the later ones (1969-1983) were 0673 and 0973. The '3' in each case is for the 12" size (1=8", 2=10", 3=12", 4=15", 5=18"). Now it just so happens that the 067* series were very common, followed by 97* and then 67* (these only ever found in Sweden), while the 097* are really hard to find. It has taken me years to collect a set of the 097* series.
But the gem in this collection is of course the No 54, its a rare 15" generation 2 model from 1911-1913 and the first one I have seen on Australian EBay for as long as I have been looking. What I have found is that in Sweden the rarity and value of these items is much better known. This wrench would sell for $500 AUD there easily; while in Australia, sellers tend not to know what they have. And so here is a valuable and rare Generation 2 bundled in with a bunch of very ordinary Bahco worth $10-$20 each.