Openlrs

Could something like this, www.hobbyking.com/hobbyking/store/__4003...h_Futaba_radio_.html

or
www.hobbyking.com/hobbyking/store/__2709...igy_compatible_.html

Be used with a devo 7e or 10?

If I have read correctly it is controlled via PPM - so yes, but you have to get some battery attached (no voltage at PPM out plug).
If you want to use it for transmitting telemetry data to the tx: actually not.

I doubt ill be flying so far out that i need telemetry, my 5.8 ghz 200mw link should give up before the openlrs does.

As for the battery that wont be a issue, ill likley have the module mounted on something or stuck on my car roof (while i hide inside in the heat).

Ill be getting my openlrs tx and rx tomorrow.
Is there any internal soldering points for ppm/ground, or will i have to make my own audio/trainer cable and use the trainer port?

You have another options to connect OpenLRS to your TX. Transmit to it using either Spektrum or Turnigy/Flysky. Could use other RX as long as it outputs single PPM. I'd go for the Flysky and use this HERE
Which would free up your PPM on your Devo for head tracker. Deviation only has one PPMin or PPMout and not at the same time.