It shouldn't be too difficult to come up with a building for Monroe's grocery store, too. That's a pretty nondescript small-town storefront building.
So in addition to the Siesta Motel, it should be possible to come up with the laundry with the apartment over it, the grocery store, the Black and Blue Eagle bar, maybe the Elks' Club building, and, since they do make HO-scale mobile homes, even Joe Aguirre's trailer office.