As far as I know, nobody makes 
jump traps anymore,  and very few 
people use them (that I'm aware of)
Instead of leaf springs with eyes on 
the ends of the trap, they use a 
leaf attached to one end of the frame 
and it goes across to the other end 
inside and torques upwards to 
shut the jaws.  More compact than 
a double long spring trap, kind of 
an ancestor of a modern coil spring 
trap. 
Some years ago I bought a box of 
old traps from a man that was cleaning 
out his father's outdoor goods 
from years ago, and there was a 
few of these Blake & Lamb #1 jump 
traps in the box. Most were usable 
as is, but one is missing the pan
and arm.