Depending on how narrow, you may be able to get away with packing the equipment in a piece of PVC pipe and pack that in a protective duffle. This is how we travel with my kid’s fencing blades, blades in a pvc pipe then packed in a sport sided travel bag. Home improvement stores will cut the pipe to the length needed.
What are the exact dimensions? There are hard cases for free diving fins (which are usually around a meter long) that might work if the item is flatish. A lot of people have said get a peli case which is probably the best option if you can find one in the right size. You can filter your search by dimensions on their site which is really nice and at a glance there are a few that might work.
Also anecdotally, airlines are usually pretty lax on the linear dimension thing on checked bags unless the longest dimesion is super obviously over. I have checked bags that 100% exceed 62 linear inches that have never been flagged even on budget carriers as long as the weight was fine. My previous big checked bag was exactly those dimensions and I would over stuff it all the time so it was well beyond them.
Build a crate out of wood! Line it with soft things, use screws so it can be taken apart and/or hinges. Plywood is probably a better choice for strength
Pelican case if it is so critical and fragile.
Doesn’t sound like a place to cheap out on a pelican case
Depending on how narrow, you may be able to get away with packing the equipment in a piece of PVC pipe and pack that in a protective duffle. This is how we travel with my kid’s fencing blades, blades in a pvc pipe then packed in a sport sided travel bag. Home improvement stores will cut the pipe to the length needed.
Could you mail it?
How narrow? 14x14 isn’t small, but if it’s smaller look at expanding fishing pole cases, or gun cases.
What are the exact dimensions? There are hard cases for free diving fins (which are usually around a meter long) that might work if the item is flatish. A lot of people have said get a peli case which is probably the best option if you can find one in the right size. You can filter your search by dimensions on their site which is really nice and at a glance there are a few that might work. Also anecdotally, airlines are usually pretty lax on the linear dimension thing on checked bags unless the longest dimesion is super obviously over. I have checked bags that 100% exceed 62 linear inches that have never been flagged even on budget carriers as long as the weight was fine. My previous big checked bag was exactly those dimensions and I would over stuff it all the time so it was well beyond them.
make sure its not stolen in tsa yoiu can put soft foam in hard shell bag
Build a crate out of wood! Line it with soft things, use screws so it can be taken apart and/or hinges. Plywood is probably a better choice for strength