2016 389 ISX 2350 Rebuild or new engine?

I got a question for those who may have run into this or have more knowledge than me.
I have a 2016 389 with an isx 2350. When I bought the truck...it had been "rebuilt". However, the paperwork was in french and I'm not bilingual. But I did see a new head and some other parts on the paperwork.
Here's where the problem lies.
About a week or so after running the truck, I found out that someone had put in the wrong air filters. They were about 2 inches too short and we're sucking air straight past them instead of filtering.
I immediately changed the filters and oil and hoped for the best but after submitting the oil sample....there was substantial silica numbers. Also some metals.
I pulled another sample after the oil change and the silica was way down but still some metal wear.
The next sample had next to no silica and lower metal.
Everything seemed ok until I switched to synthetic oil and my filter plugged. Changed the filter and it was fine again. But i was going through oil.
Went back to regular 15w40 but still going through oil since then and on a cool night you can see the haze coming out of the exhaust. Also if you take the oil filler cap off...there's blow-by. Not massive amounts...but it's def there.
I guess my question is this (as I'm not a HD mechanic by any means):
Can I in-frame this engine or would a drop in be a better idea? I'm not sure if the silica levels could have damaged the crank at all?
If I do in-frame...I would also do new head and probably cam.
Anything else that you would do that wouldn't normally be done in a rebuild?
Thanks

 

About a gallon every 1500-2000miles

 

I forgot to mention in my post that my oil pressure is still good. Idles hot at about 22psi and running down highway at 35-40

 

That's why I was wondering if a drop in would be a better choice. Regular inframe around here with new head/injectors is prob 33g. If it gets deeper....itll ad to that cost. I can get a pre-rebuilt engine for about 39g plus R&R.