If you remove the stock from the action, the overall size can be reduced. A local gun shop should have a spare empty rifle box you can cut down for posting. If you don't have spare bubble wrap, screwed up newspaper (lots of it) makes good padding.
The open sights look to be present on your example and if they are undamaged and uncracked, they are a desirable item on an early Meteor.
The piston buffer washer and breech seal usually turn to powder on these old rifles, so that is common to see. Protek Supplies in Bognor Regis sell spares for old BSAs including Meteors if you want to get this old classic up and running again.
Kind regards,
John
Currently looking for Baikal Makarov pistols with the following prefixes to the serial number: 98, T01, T09, T21, T22
Prefer boxed or cased but will consider loose examples too.