Here's an update on the email results.

As I said a while ago (02-20-15), I sent an email to .
Later that same day, I received a reply!!!

In the reply I was asked for more details regarding what I want
(specs) in the filter. I told Sneva the frequency (276Mhz), etc. I have not
received another reply. I sent another email to Sneva, but still no reply.

I asked Sneva if he (assumed) can't make the filter, please let me know
so I can look for another source. Still no reply.

Hi,
UPDATE:

I finally received a quote, $185.00 plus $20.00 shipping. Since this
filter has to be custom made, the price is high.

John