What do you mean by needing "new" calipers? Just get a rebuild kit from the parts dept. Aren't re-manufactured calipers all just rebuilt and refinished OEM's? Are there outfits making true 3rd party castings?

The Toyota kit has new square-cut seals, new dust boots, new C-rings, and some rubber grease (pink silicone based stuff). The kit has all the stuff to do both front calipers. Its really pretty easy. If it's due to a frozen piston, you'll probably need a new piston. I rebuilt both my fronts. Both needed it a different times and in both cases it was 1 stuck piston, and I had to replace those pistons. They were pitted. I bought new pistons from rock auto and they were centric brand, about $9 each I think. I measured them against my OEM pistons and they were the same size. If you try to get just the pistons from Toyota, they'll probably say they are only sold as part of a new caliper assembly. Not true. There another older thread on a rebuild and has the piston part number. I gave that to the parts guy and it came up as $60+ each (!!). Hence, my decision to go with rock auto. I just got home from a family trip and have about 1000 miles on my rebuilt calipers. No issues except from rust (see further..) which was my fault.

It's an easy process, just a little tedious if you clean up all the grime and any corrosion, and it's a bit messy. I soaked mine in some metal rescue to ensure I removed all the corrosion (there wasn't a lot). Couple things I learned:
1. Get a tube of the toyota pink grease. The pouch that comes with the kit is tiny. Maybe I used too much, but that pouch wasn't enough.

2. You should probably count on painting the calipers. The OEM's must have some kind of anti-corrosion coating and I must have removed it when I cleaned them up. I didn't realize that. Now there is rust staining. Right now I think it's just surface rust, but I don't want it ti get any worse. Now, I need to take it all back apart, clean off the rust, prep the calipers and paint them.

Now having said all that, if you have damaged calipers, I'd pull some off a wreck at the junk yard. The only issue with that is if there are enough yards nearby to where there could be a 4th gen out there.

Trying to buy new and there's a wait list at your local dealer? Order online from a different dealer?