Italian WWII Helmet

I picked up what I'm pretty sure is a WWII Italian helmet. Condition not the best but not terrible either. Exterior looks pretty good, interior has a lot of rust breaking through the paint. Liner is complete with the exception of the strings which hold it together. It is pliable but does have a few tears/cracks. Leather strap is torn in half but all there. Buckle is solid rust. It also has a web netting which is in very good shape but I do not know if it is Italian or US. There is a 2 inch crack in the helmet which is not separated or dented.

For display purposes, it is fine. I don't think I'd do anything to the exterior but the interior has me concerned. Should I attempt to get rid of or minimize the rust? Patch/sew together the strap? Put a new string in the liner? Weld the crack or let it be?

I know these helmets are probably the least collectible of the WWII helmets but as this one appears to be period and not post war, I guess that makes it a bit more collectible than say a better condition post war.

It has a P 69 stamped in the rear metal near the rim. Doesn't show in photo. The liner has a large 58 created by making pin holes in the leather, located under one of the strap connections.

From what little information I could find on the web, it has the less common vent holes without the flare around the edge.

Anything anyone can tell me about it would be appreciated.

https://www.milsurps.com/images/impo...zckryele-1.jpg

https://www.milsurps.com/images/impo...zgmgoczf-1.jpg

https://www.milsurps.com/images/impo...4wpayu6x-1.jpg

https://www.milsurps.com/images/impo...7sik4zd4-1.jpg

There's something you don't see every day...I don't recall last time I saw one here.

Italian M33 or Bulgarian M51? I'm not sure.

It looks like a m33 to me, but hard to tell with the net on it. The net looks like a us m1. I could very we'll be wrong too