Macro B programming is not in the Hobby version of Mach4, but is present
in the Industrial version. The list price for Industrial is $1400.00 which also
includes other industrial features for more complicated machines, and
access to telephone support.
I do not recommend a wireless pendant for any CNC control due to issues
with loss of control. That being said, there are several that advertize Mach3
support via USB. It is likely that the more basic controls on those would
also work with Mach4 or could the made to work with some scripting.
VistaCNC.com offers wired pendants that understand Mach4.