Bought a universal electronic flasher relay from Canadian tire (product number 20-1032-0) made by Tridon. Cost $9 plus change
Works perfectly with the bike. But original plug needs to be spliced and connected directly to the flasher.
Hopefully this helps someone in the future.
Personally I'd leave the bikes wires alone and buy the proper flasher. I have the one listed above from Cliff, works fine with my mix of LEDs / incandescent lamps. Fits in the factory rubber grommet too!