[Drake] TIS-153 FET Specifications or Spares?

[John Chesley]

Hello,

In troubleshooting my Drake R7 receiver, I have isolated a bad FET, the
TIS-153.  I have not been able to cross reference this part with a modern
device and was wondering if anyone has the full specs on it.  There are
others that will work, but wanted to be sure of matching the specs closely
with a replacement. Or better yet, does anyone have any spares for sale or
can tell me where to get them?

Thanks.

John