Need a new fuel sending unit,where can I find one

For my 1979 D100 pick up,,Yes I know everyone will say Rock auto and all the local Zone type stores..I've tried them all...I lifted off the bed to get to it and it has 2 electric pins and 2 hose connections..and is held down by 5 screws ,not the round spin on clamp that everyone is familiar with..JC Whitney was close but the hold down was wrong..Any ideas ?

Last one I bought for my Ram Charger was dealer.Mine the supply was rotted.Had too drill a few of the screws out also as they just snapped the heads off.My buddy that was part mgr sold it to me for like 70 bucks.They werent making them anymore at the time.Rocky

TK-0277 they have it here: www.jimsautoparts.com

Be very very careful about buying from Jim's. They have a BAD,BAD,BAD reputation around here. Did I mention that Jim's has a BAD rep.