Need help with a Mk IV mod 1 high altitude helmet

[seabolt92]

I was just wondering if anyone with more experience could help me with this one. I believe this is a Mk IV mod. 1 flight helmet. Everything looks ok to my untrained eye, until it gets to the tag underneath. It appears to be handwritten, rather than printed? 2701 serial according to a quick seems to imply a 1961ish date. Ive seen other helmets not have a handwritten tag, with dates earlier than this. Any help would be appreciated! Thanks!

 

[HUD69]

If the inner parts where replaced by new, it might be an explanation why it is handwritten.

Furthermore, it is missing the microphone, the cables and unit from the side of the helmet and the neck ring. 

 

For more info see this thread on USMF:

Mk.IV helmets