I have also been very pleased with International Crystal's crystal products.
They are properly "aged" prior to shipping which takes a little longer, but is
worth it.
One word of caution, however. Their database may not reflect the Drake manual's
recommendation to use a 300 kHz offset for the 30m crystal in the T-4X series of
transmitters to avoid spurious emissions. At least this was still the case when
I ordered a 30m set about five years ago. The crystal frequency recommended by
Drake is 20.8 MHz for use between 10.0 and 10.2 MHz with the T-4X series. The
"zero" on the dial corresponds to 9.7 MHz so 10.1 MHz will be at 400 on the dial
scale.
73,
Harvey, N6MM
References:
T-4X/T-4 manual page 22
T-4XB manual page 25
T-4XB/T-4 manual page 24
T-4XC manual page 2-4