Id rekon not. Even if the devices would allow functioning on UK frequencies (currently Channel 38, recently moved from channel 69) you still need a license from UK regulatory body (JFMG) to turn them on. There are 4 useable unregulated frequencies on ch 70 but these are very congested, and very close to the 4 G mobile broadband networks (newly sited on ch69 next door) so theres a real risk territory.
I dont know about other countries, but Im sure that most will have regulatory bodies controlling this type of thing, so finding a universally accepted device will be difficult, not so much from a frequencies point of view and many will work across a very wide range, but from the legality point of view.
My advice would be
1) buy kit licensed for use in your territiory.
2) Hire local kit abroad when you need it, which will be specced to work on that countries frequenciies and come ready licensed if from a reputable hire outfit.