I can't assist with your query David,
There was a British made R103 (never sighted one) that is more likely to have some connection to the R107, but I've no idea.
Thanks for the heads-up on the ebay sale...always interesting to see gear you have coming up for sale.
Mine has been converted (not guilty) to 240v and operates nicely.
I like the Canadian Broad Arrow being still visible....I know Chris likes my 'mad brass polishing' antics
http://www.royalsignals.org.uk/photos/r103/r103.htm
http://www.duxfordradiosociety.org/r...r103/r103.html