LED lamps (indicators)

[Gadget]

I have a Chausson Best of Ten, on a Mk7 Transit base. I have changed the bulbs to LED except the indicators. Although I use canbus error-free bulbs the frequency of flash is too high; I have the same bulbs in my VX220 but use an electronic flasher unit which flashes at the correct rate.
1. Is an electronic flasher relay available for the Transit? If not--
2. What resister value do I need to get the correct flash rate?

Thanks.