[Arran]

 There would have been a 25 cycle version of the 37-116 sets, I'm not sure if they still added the suffix "A" after the model number. Point in fact there were 60 and 25 cycle versions produced in Canada and in the U.S, if you look at most period advertising for the Canadian market they offered 25 cycle versions of most makes and models at an extra cost, although Rogers built sets seem to have all been built with 25 cycle power supplies. The extra  capacitors, were added for extra filtering to contend with the coarser ripple, these days you could probably leave them out to no ill effect since there are no 25 cycle power systems anymore, yes I think using 630 volt film capacitors will work, if you want to bother with them. Most of the 25 cycle versions of other radios I've seen just enlarged the capacitance of the main filter caps, or added an extra one, they didn't normally shunt a lower value cap across a filter choke. 
Regards
Arran