You might consider...
Just making one for a few pennies.
takes about 45 minutes.
My wingtip mounted VOR GS works perfect. I use a splitter.
I'd put the comm and Xponder antennas on the belly if I were you, as most folks have been less than pleased with the Archer comm.
For marker beacon on my Val INS 422, you can use stripped coax, or length of copper foil tape in the wingtip bottom, Mine has a stainless hinge pin with a coiled end for the terminus bonded to the wingtip bottom under a couple of layers of cloth tape and epoxy.
Use search for the plans.
Regards,
Chris
