The NP203 is identified by several features.
1. The transfer case is made up of 4 sections bolted together: a range box (used by various companies to make a 't-case doubler' set up to get even lower low-range for rock crawling), the chain case which houses the chain drive to the front driveshaft output, the differential housing, and the output housing. The front 2 sections are cast iron, the back 2 sections are typically aluminum.
2. The overall length is about 22" - 23" from the face of the case to the rear output yoke centerline.
3. The shifter is a somewhat complicated box that actuates the 2 levers on a single shaft on the side of the range box section of the 203.
4. The model tag (if it still exists) will be found on the front of the chain case above the front output shaft. It will list the model number, the manufacture date and the gear ratio.
your far left is a mated gear only NP 205 ,and Id say that other is a borg warner chain drive hydraulic pump 1346
with out an adapter and longer shaft etc etc you are gonna have a hard time glueing that together ..plus mounts and linkage to boot...
I have a brandnew rebuilt 203 in the shed ....hate to ship that anywhere yuck ...freight cots ya about the price of the T case