The best unit is an H/T with a true signal strength meter and an attenuator of some kind. Arrow sells them and I think Adept has an attenuator.
If you want to go on the cheap this one you can cobble together, mount it in a box and secure it to the Yagi with Velcro:
https://www.west.net/~marvin/k0ov.htm
I've used the K0OV attenuator with success and a TH-F6A.
The cheap Chinese H/T's
"DO NOT" have a true signal strength meter! It's either all on with a signal
or all off.
Now some say if you use earbuds with a mono convertor plug you can detect the signal strength with your ears but if your hearing is a bit off
a true signal strength meter is more helpful.
If you plan on doing APRS tracking later on get a D72A and you can do anything with it on the Ham bands. A TH-F6a might have the potential to do the "animal trackers" on the B band with an appropriate 200Mhz Yagi. I did some preliminary tests but not a rigorous field test. The F6A of course could RDF track the TeleMega.
If you're going to do RDF and APRS on the Ham bands only and not mess with animal or Com-Spec trackers, a D72A or a Yaesu used
VX-8GR (only if you can get it at a good price used) would be likely candidates. If the $$$$$$ are unlimited a D74A could do just about
anything for you and then some but costs are extremely high for that one.
The thing with the GR and 72 is the ability to put the rocket waypoints on a map live and compute a live navigation solution on the fly.
If you want the potential to do that, that's the rigs you want to consider. Kurt KC9LDH