If you’re a Chaos-Family or other non-commercial/community event you probably want to ask C3ROC for help: https://twitter.com/c3roc_
Also; channel 1-8 PMR446 radios are cheap. They do for most small applications.
Also; just get a HAM (Amateurfunk) licence. Especially for high-power/long-range applications. Really. Much less pain and money involved than getting PMR conform devices and matching licenses.
The HAM radio exam is easy enough. Read trough these Books and you should be good.
Infos for Switzerland and Germany.