I searched AllData, and couldn't come up with anything to help you out. They have it listed as a "module" rather than a relay of flasher. There is also no part number listed for it.
As most trailers use the brake light as the turn signal, and our cars have separate bulbs, an after-market unit is installed to combine things. I'm not familiar enough with them to know if it may be wired from a separate power source which takes care of the extra current draw which would normally cause it to flash too fast, or not.
Black 2000 SSEi, Silverstar Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, drilled 180 degree thermostat, Intense FWI, PCM, shift kit, and 3.4 Pulley. Solid front mount.