Hi Mike. RF Parts lists the MFE521 in their Misc parts listing. Price $5.95 ea. BUT, minimum order is $25.00 from them. Checked Mouser and no listing whatsoever. I agree with you on the Asian clone parts being questionable, certainly at analog VHF. While leaded is going away, some of these parts can be found in surface mount and if a 1206 size can be worked with, no luck in this case so far.

Hope this helps.

Paul - W2NMI