Help with parts lathe identification. Odd parts

I picked up this lathe primarily for the tooling and planned on parting most of it out to make some of my money back. After tearing it apart im noticing quite a few differences from my lathe.

I dont want to sell anything thats not right to someone screwing them over, so before i part it out can someone help with identifying whats going on here ?

First is there is no serial number. The thickness of the bed is ~.080" thinner than my other lathe. THere was also spacers between the lead screw brackets and rack to the bed. I assume at somepoint someone had the bed reground ?

Second is the spindle. I have searched and searched pictures and cant find anything like it. There is removable caps on the head stock casting and thrust clamps with needle roller bearings for the spindle. On the end of the spindle there is threads and there was a seperate gear on the shaft that had a staking in place to keep the gear from coming off.

The brass tag on the side cover says model 415 YC. I have no idea if its original or not.

one more of the head stock.

yes, that headstock is heavily modified.....as such its parts are pretty much its parts...but if it works well sell it whole.

Also

It came with 2x 54x18T compound gears. one is thinner than the other. It looks factory, not like anyone modified it, but hard to tell.

Any reason for a thinner gear ?

was planning on selling off the duplicate gears, just wanted to know before doing so.

hmmmmm...dont think thats factory...likely a special purpose, but dont know what....possibly for a different machine altogether.

Can anyone tell me what this carriage lock is from ?

The one on my other lathe looks like a milled block with two pins pressed into it, as do all of the ones on ebay. Is this correct or from a earlier/later lathe ?