you do realize that it looks awfully a lot like a
D.H. Russell Canadian Belt Knife?
"...which has been in production since 1957..."
http://www.grohmannknives.com/pages/r1s.html
and taking into account thar Carl Schlieper (eye brand) was founded in 1898
and went bankrupt in 1993.
so if indeed it is a product from eye brand ,
then it would have been a copy made between the years 1957 thru 1989 (an amalgamation took place).
interestingly enough,
take a look at comment #24 of this thread
which spoke of a copy "marketed by *Herter’s around 1970..."
http://www.canadiandesignresource.ca/sport/grohmann-knife/
in fact, it wouldn't be unreasonable to assume the possibility of your model
being a german made product of that era.
hope these assumptions might help you some.
good luck!
*
http://www.rmurphyknives.com/store/media/Herters-1979-Catalog-Page_83.pdf
this one says,
"
Original Belt and Boot Knife
"Hand made in Solingen Germany
13930
"
whilst another etched, on the reverse side
"
Original Belt and Boot Knife
Richard Sabinox
Hand Made Germany
"
it wouldn't be surprising, if these german copies were simply a case of being relabeled?