Rear Brake Calipers needed, can’t find

I have 45k on my 23 Tundra. Noticed the rear brakes are completely worn out, front are fine. I do 90% towing so I just blamed it on that. After doing some digging it appears the caliper pistons are seized (I’m totally aware of the e brake situation it’s not that). Even after taking the caliper off the piston will not go in and out. It appears nobody makes an aftermarket caliper for the rear! Any guidance or help locating two would be appreciated.

 

Did the piston move in and out with the parking brake motor?

 

They aren't available through any of the dealers that sell parts online? Or are you specifically looking for the generic/aftermarket stock equivalent caliper?

 

I’m looking to buy them anywhere I can get them quickly. It looks like I’ll be going to the dealer on Monday and hope they are in stock.

 

It wouldn’t move in or out. Even after I disassembled the caliper it was almost like the piston was just too big. Turning the t47 hole on the back wouldn’t do anything either.