Shoup includes shipping if you spend enough ($200?) but mostly deals with bigger implements. Wider availability is Sloan Express, I think in Illinois. Don't know where you live but I have two or three lightly used moldboards as well as three of the new weld-on triangle corners that go near the landslide. Also have three "frogs" that everything bolts to and I think a 101 owner's manual. They are good medium duty plows that do a good job but pull a little hard. Part numbers are stamped on all the backsides.
I'm pretty sure Oliver parts aren't going to fit on a 101 Ford plow but if you ever run across an old Oliver in good shape, buy it. They are well made and pull easy. They did make for lots of companies as well as their own brand. White bought them out but it's hard to find Whites in two or three bottoms. Oliver did make the next two sizes up of Ford heavy duty, large frame plows, or at least the bottoms, and those are a great buy in the 80 HP+ category. They are heavy plows and old Olivers bring good money.
A good thing about the Ford 101 plow is the ability to remove bottoms if you can't pull it. All the frame parts have the same holes so it's easy to take off. At auction, a four bottom might sell for half the price of a two or three bottom when all you have to do is take off what you don't want. Easy-peasy.