Mystery - This watch pictured below is posing a challenge to identify the maker. Prior to posting here I have done lots of digging but am coming up blank on info and watch remains unseen anywhere else. This watch movement would have been made by a Swiss maker for the high end Canadian jewellry store Birks for there in house line known as Rideau. They had enough influence/buying power that all reference to maker is not on movement.
The marks “Birks”, “17 Jewels”, “Swiss” is there. Inside bottom case reads “Pioneer” (Assuming that’s Pioneer Watch Case Co. but almost zero info out there on them), Scratched in mark read “R 3538 L” (Model/Movement number?), Also, scratched in, what looks like “DG 486” (assuming a previous service date Apr 1986?), On bottom of lugs scratched in “291” on one and “154M” on another.
It’s possible this is a rebranded version of an existing model in a watchmakers line. There are some Gruen models I have seen from late 40’s early 50’s that are close only. It’s also possible the Swiss movement was put into a case chosen by the jeweller that didn’t exist in the line of any maker.
The closest visual that I am identifying with is Gruen watches (a 420 or a 422 movement?) Also, some Longines look similar. Do any of these clues and pictures help any members here make any guesses or conclusions? Please let me know if anything comes to mind, any ideas appreciated. Thank you.