I am Oleg UR8LV (ex EM1LV)
I would like to propose you hand made antenna for 464 MHz.
This is collinear 2x1/2 vertical.
SO-239 or N-female for you request.
Antenna without fastening for weight, for cheap shipping.
Stainless steel.
Typical band for SWR=2 about 40 MHz. With clear SWR= 1.05- 1.1 on center.
For example on foto: SWR=1.75 from 450 to 485, center 464
I can make same antenna for your personal frequencies 400-480 MHz
73!