sorry guys, I get confused between these freq counters, the one for the MFJ 
is the MCount, not the freq mite.
Just going over the text file now.  It looks like you need:
an NE556 dual timer (there has to be modern versions of that chip, it's not 
special)
You need a CA3240 op amp
A temperature stable reference diode LM336 (common like air)
and that's all the IC's required for the VCO...a few other caps, resisters 
and a few transistors along with a calibration pot round out the circuit.

Information about the MCount and obtaining one is found here:
http://wb9kzy.com/mcount2.htm

If this was the oh so special chip, it's 3 bucks to buy and easily available 
apparently.
They're sold out of the MCount2's, however, I suspect if there was interest 
they might be had.

And yes, an MFJ 249 was used as it's very similar to the 209.
Anyway, this is all well within the reach of most blind hams to obtain and 
have built or modified.  No problem.

73
Colin, V A6BKX