After breaking a few tow hooks on my EPO Foam FPV planes, I came up with this collapsible tow hook. It requires a rectangular hole be burned (use a soldering iron) in the foam about 1/3 the distance from the wing spar to the nose. Then glue it in with Beacons FoamTac. Here are the parts:

Printed Parts
Tow_Hook_Base_v3.STL

Hardware
8mm O.D. x 5mm I.D. x 31mm L Aluminum Tube
M3 x 20mm Button Head Screw
M3 Hex Nut

You can find the aluminum tube material at a local hobby store. Then follow the picture on drilling and shaping the tube befor assembly.