What year are you looking at? Something like a 57 Ranchero would bolt right in the same as the wagons in that year but when you get up to the ones based on the Torinos in the 70's it would be way too wide.
You just have to think about what car the Ranchero was based upon in the year the rear came out of. You have the 50's models based on the Fairlane, then the ones in the 60's also based on the Fairlane and then the later Torinos/LTD II models. I don't believe that the Falcon Rancheros ever had a 9 inch rear but they would fit great if they did. I just know the 72 and newer Torinos and then the LTD II rears are big time too wide.
I used a lot of these 9 inch rears in stock cars. They were easy to get because they were too wide for anything else. I used 5 inch offset wheels with 10 inch Hoosier slicks to get them anywhere close to being tucked under the fenders and that was with a wide aftermarket body I think the width was somewhere around the 60 inch mark and you need something closer to 54 inches
9 inch ford Any 9 inch rear end out of a 1957-1959 ford fairlane,rancharo or wagon will bolt right in to the maverick/comet you can still find them on craigs list for not to much money there is a guy in oregon that has two for sale for 300.00 for the pair and they are complete so I hope this helps you.
This was just to show that they are out there if you know what to look for I agree shipping from oregon would be to much but if there is rear ends availible out here then they are availible closer to you.