Those clothing materials were banned. I found some of these caps were not as warm as the wool cap, but I’ll mention I did find a wool cap on a Navy post and picked one up. Apparently, still the preferred headgear for merchant mariners.
Also, wool sweaters are preferable for the field as they too provide flame resistant properties.
Lamb also tastes great! Don’t skip the marrow.

Never seen a lamb variant of an MRE. Did however acquire a halal meal with lamb as the main meal here: download/file.php?id=220&mode=view