A number of new radios with high-performance front ends use 2SK1740's
in the mixers. (e.g. the 756Pro3, Omni 7n - in fact you can find their
schematics on the web). If I wanted to grab a couple of these for my
experimentation, where could I buy them? They're almost certainly
surface mount but that's OK.

The previous generation part of choice seems to be the 2SK125 (as
illustrated in the ARRL handbook) and I'd like to find some of these
too but these seem to be obsolete.

Any other parts to look at? Sabin was using the 2N4416 (common-source
but same idea) in 1970. Today would a J310 be about equivalent?

Is the actual part number less important than matching when it comes
to performance?

Tim N3QE