You'll have to shoot through the old bulbs with a multimeter to see how many ohms of resistance they have. Get an equivalent resistor but keep in mind it has to dissapate a great deal of heat energy, I smoked a little 1 watt res. so you better look for a higher wattage one. I eventually found some bulbs to use so I abandoned the resistor idea. The flasher is some goofy toyota only crap so I have no idea where to get an electronic or heavy duty one, sorry I wish I knew.

1986 4X4, 1991 22RE, 5.71 gears,ARB Rear, aux fuel tank, 3mm O/S TB/intake, engnbldr cam, LCE header, magnaflow w/2.25 exh. custom 4 color paint job :-P 33X12.5 Goodyear MT/Rs