Shimano 105 6-speed indexed shifing components

For the Benotto kid's bike I was looking for some indexed shifting components. The SunTour parts may be the original components from the 1980's, but in case my or someone else's kid is going to ride this bike, some better components have to be used. Friction down tube shifters may be a bit too difficult to handle for an 8 year old kid.
Via "Marktplaats" I found a good set of Shimano 105 components. Not exactly the same age as the bike, but close. These 1050-series have been produced in the second half of the 1980's and belonged to the first indexed ("click") shifting components. The down tube shifters (I'm only going to use the RH one, since the bike has a single front chain wheel) and the rear derailleur belong to the same series. Although finish is not as nice as the more expensive Dura Ace, the weight is higher, it wears a bit faster, works in the same way, there is much better compatibility with other parts and the price of the components is much more attractive. It will work perfectly with any (Shimano) 6-speed multiple freewheel and derailleur chain. An excellent choice for this bike, especially, because the finish is shiny silver.