Do I need a kingpin plate and pin?

makes sense when I bought it the wood in the center was torn out and I could see the rust and all sitting on top of the plate. the old man I got it from said it was like that for a while. I can imagine being up here in the northeast dealing with rain, sleet, snow, salt etc she’s taken a beating.

 

Some of the details in your pictures I cannot make out. Here is a picture of a worn out pin and a worn out plate in my scrape pile. If yours is working in ether one or both of of these directions it is time for a a whole plate and pin deal.
Would I be afraid to pull a trailer with a hole rusted in the plate. No, not if the rest of it is good.
If the rest is OK
Would I put an annual inspection on that trailer? No.
Just my opinion and some pics of what to look for.

 

The pin is good not damaged. It’s the plate that has me concerned. And if I’m going to replace the plate might as well do the pin as well. I have not put a level on the plate but I am pretty sure it will not be leveled just like the one in your picture.

 

That plate is going to look 50 times worse from the inside under the floor. I would definitely replace it all. Sounds like you're getting a decent quote for the job and you already have put some money into the trailer. I say do it ASAP before Winter gets here.

 

This is what they look like after they fail.