How "vintage" is this Collins?

[COSMO]

Looking for any input from the experts on my recent estate sale find. I paid $10 for this Collins at an estate sale yesterday, it weighs in at just under 2 lbs. I found a couple of these on-line selling for $35 to $50. Not sure if these prices are accurate.

So, here are my questions - About how old is it? what is it's true value, and is the sheath original?
I appreciate any input - here are the pics
Cosmo

 

[Yankee Josh]

I'd say 80's if I had to guess. Someone on here knows for sure and i bet they'll chime in.

 

[junkenstien]

Does it have m1 1/4 stamped on it?Would say 80s or 90s too but i believe mann was in business till the early 2000s if i recall correctly. That is if you think mann made these like i do.

 

[COSMO]

J junkenstien - Thanks for the input, I looked it over very closely and do not see anything stamped on it. Unless it is under the "Collins" sticker.

 

[Hickory n steel]

The sheath looks like your typical cheap Rothco GI repro.

At least of these hatchets has shown up on this forum over the past few years and I believe the consensus was 90's or early 2000's but don't quote me on that.

I don't know what you'd search find the thread/s, but I'm certain there's been a thread.