When I say travelling, I mean the actual physical process of getting to and from your destination. From what you say you are staying at all-inclusive and these days nearly every place I have stayed in has had a small fridge in the room, and if not, they are air conditioned and so I have sometimes just left the stuff in the room safe.
In the past when the room did not have a fridge I always spoke to the reception and they always allowed me to put what ever spare stuff I had in a fridge which they then either allowed me access to or they brought to me. I have not had to do this for many years now.
As at home I just leave the my pen in my room during the day, or if I know it will be a long walk back during the day I keep the pen in the shade, and as above, either in a wet flannel, or next to a large bottle of water – also in the shade. I know DSN’s will cringe with horror and try to strike me down, but it works, is simple, is almost the same as being at home, so no new regime to learn.
If you want to buy, then my advice is go cheap as you probably only think you need it, in practice insulin keeps well enough out of the fridge.