The biggest issue is in fact insurance.

The RMSD is 500 std iirc but can be increased.

It is ABSOLUTELY legal to post. I do not believe RMSD excludes air rifles BUT your biggest issue is packet max dims and mark the package NOT BY AIR.

Breaking the action down - out of stock mod off, bottle empty may accommodate this etc.

It is also entirely up to the seller to decide if he posts or not and any other conditions of sale they might wish to add.

As frustrating as it may be, thats the deal.

Just as bad is posting pictures on AGBBS is such a PITA.

OR sales don't edit the first post when an item is sold and its a long thread...

There's plenty to frustrate