Travel car seat 6 year old

[RIPVPROG]

Hi
Day to day DS uses a cybex platinum t solution, we have taken it away with us in the past but it's heavy and I don't trust airport staff not to throw it around so we end up lugging it to the gate. We're in Greece this summer (islands) and will be hiring a car from the airport. I'd really appreciate any recommendations for a decent travel seat, that's portable/foldable but still safe. We won't be doing any motorway type driving but I'm still not comfortable with some of the very flimsy options or a booster without a back.
DS is just 6 and 124 cm , budget under £150 if possible

https://www.maxi-cosi.co.uk/car-seats/tanza-i-size?color_swatch_id=5982&utm_source=google&utm_medium=cpc&utm_campaign=PMax%3A%20UK_pur_CRS_shopping_NEW&utm_id=17678645666&gad_source=1&gclid=CjwKCAiA5eC9BhAuEiwA3CKwQjzCaM4jIotj4WID9AhkeN7A65i_tIFXsxg0jqqx4L1g9ksFABD7tRoCA2AQAvD_BwE

I don't know anything about the seat but is a more well known brand

You could just buy a new lighter weight high back booster seat and store it in its box for travelling.

We travel with an axkid minikid which is about 14kg. Luckily you get rid of them to oversize baggage quickly.

We have a Trunki boostapak for our 6yo, for travel, it's ideal

Yes I'd look at the Maxi Cosi Tanza i-size as linked in the first comment. Maxi Cosi HBBs tend to do well and it's foldable, in budget and will weigh less than your Cybex. Folding up should protect it from damage in the hold as well - you can also get car seat bags for them which will have loads of extra space and you can pad it out with things like towels and save space in your luggage.

Thanks! The maxi Cosi looks good, we've already got a carseat bag (that often also carries a giant stuffed cuddly tiger...)