Peli make great cases, but they are a heck of a heavy, can be large for the payload volume, and so can be costly to use for air transport plus they can take up a lot of space in the hire car at the other end.
It would be worth seeing if there is a maker of flight cases near to you. I don't mean someone who sells bought in ones but someone who actually has the skill to build one well. I use both Peli and flight cases on a daily basis and while the Peli cases have their place they are over specified and over weight for carrying a simple rifle/scope setup on a plane. Musicians are travelling around the world every day with delicate gear in flight cases, plus the gear is loaded in and out day in and day out, and the flight cases do the job just fine.
You can get one made to your exact requirements plus it should be possible to design it to be lightweight. I had one built by a friend who is in that business and the requirement was that the rifle, scope, bipod, sling and case should come under the 12kg that Easyjet allow you when you book a firearm. He designed and built a case for me that comes in just under the 12kg when loaded up and you can jump on it with no ill effects to the case or gear inside.
Going the custom route will not be inexpensive but you will get exactly what you want, you will get something suited to the task and you will save on the excess baggage charges.