I switched over all the IR boards for the Chief Delphi team to use the 56 kHz Vishay TSOP IR part. This is just a matter of desoldering and removing the existing 3 pin piece and replacing it with the Vishay TSOP 34856. The units still work with the limited number of IR remotes tested (2) and still have jamming when both units are pressed at the same time.
There is also a Vishay TSOP 7000 IR component that works at 455 kHz. My searching revealed that this is an uncommon remote frequency and I couldn't locate an inexpensive remote
that works at that frequency. I will post the Vishay TSOP 7000 IR pdf for reference.