[updated:LAST EDITED ON 19-Nov-02 AT 05:14 PM (EST)]you should be able to find some blackjack, heddman, dynomax, or hooker's for it. don't be fooled by the year-models they list - anything that will fit a '72-'79 should fit, and not just ranchero - torino, LTD, cougar, t-bird, elite, with 351M or 400.
example: i had heddman's on my '75 351W ranchero. i think they were listed for a '73, but i'm almost positive they would have worked for a '77-'79 351W as well as my '75 or a '73 - the frame, suspension, firewall sheetmatal, etc. is the same on all of them. also, the listing said "no power steering" but i got them anyway and they were nowhere close to the power steering!