They made 6.5M of them and there are hundreds of thousands still in this country. Many are NRA sale guns which were either untouched new 44 guns (I have 2) or fresh rebuilds (I have one). Most are in circulation but many are undoubtedly still in Grandma's closet undiscovered. These can go for $500 if you catch the Grandma or her kids. My brother in Wash state did exactly this.
"Horses rumps" are anyone who prices their carbine above what you can afford? "No longer serviceable"? Most carbines were rebuilt and carbines in general will go thousands of rounds without deterioration of the barrel. The acceptance tests were 6000 rounds and some of these test guns were simply cleaned and sent out for issue. I'd say that the average carbine was carried by some officer, cook, signal personnel and fired very little. These are far from worn out.
"Complain all you like, but if you don't like the A/O or Inland Carbines, you'd best quit whining and work on finding an alternative." Sound advice, I'd suggest a genuine US carbine at any price you can afford.