DPX-WC-22-28-34 is a WR34 diplexer with very wide bandwidth for both channels.
Is the insertion loss for your narrowband filter too high? WZ-Series filters offer much lower insertion loss and higher power handling than standard filters.
Typical WG Filter IL: 1.2 dB
WZ-Series Filter IL: 0.5 dB
Do you need waveguide filters that can fit into tight spaces? WC-Series filters can be as short as half the length of typical waveguide filters and are also available as multiplexers.
BPF-WZ1-4764-22-8-187 is a C-Band Band-pass Filter with super low insertion loss.