Where to find an MF6-50

[McLaren]

I am looking for an obselete chip: the MF6-50, it is a Butterworth low-pass filter and was produced by National Semiconductors. Has anyone any idea where I could get some, I've looked everywhere I could think off, however this is not really my field. Thank you.

 

[Lewish]

Try these people. I assume you don't care about the price and need more than one.

http://www.derf-intl.com/

They show several hundred available from different sources.

If you need only one, you are probably out of luck.