Now we're getting somewhere, perhaps

.

As Lancaster advised, the cross is Greek. Their navy models had an anchor in the same position.
Though some sources say the Breda MS were made in Italy, many maintain that they were manufactured in Austria and assembled in Italy (to circumvent export regulations then in place) while others insist they were made completely in Austria and merely 'drop shipped' through Breda.

Is your Breda 'sporterized' or still in military form? Still 6.5X54? There may be merit in keeping it unmodified if original and in top condition. If sporterized, how much and by whom? May we presume it wasn't milled for a side plate?

New England Custom Gun offers claw mounts. They, as with any claw mounts, are rather expensive and must be installed by qualified experts.

NECG Claw Mount

Website: https://www.newenglandcustomgun.com/products.php?cat=279

Video: https://www.youtube.com/watch?v=dBA1BpYyG8M&feature=youtu.be

Navy

Greek Cross

Breda

Here's a bit more MS info: https://www.africahunting.com/threads/ma...velocity.47277/