OP if outside the US (and not intending to come into the US and leave again) why would you buy those tubes, just buy decent Harder or Photonis tubes - they are way better than those PRC Ekran grade tubes.
The better Photonis tubes 4G+ have the best autogating across all manufacturers, best shock rating, best IA, best halo, best "highlight" lp/mm, generally best EBI <<< 1 and best spectral range. Some will gripe about gain but its typically 50k.
Alternatively, give an OPSIN a go - no issues with travel at all.