unknown helmet

[BAR21]

new member old collector -- I got this camo thinking its a Parish not a Schuleter. Its longer in length than McCord and its rear seam no heat stamp visible nor is the “S” for Schuleter which brings me to Parish Production. The paint shows some age my guess be 70s to 80s camo paint. I check for heat stamp front lob no luck so I’d be putting my money on a Parish shell and of an Vietnam era. The undercoating paint is a red under the OD paint. I have seen a type of camo in Asia used before my question is is this helmet of the Thailand Army or could this be a Army Republic of Vietnam? ohhhh BTW in front lob seems a rusted area might have been for a head badge