As long as the barrel is sound, and there are no cracks, it’s fine to shoot. The pictures look fine to me. It’s chambered for 303 Savage which is not a high pressure round. However, it is 303 Savage, which is an obsolete cartridge. Buying new loaded ammunition is a thing of the past. Do you currently reload? You’ll need dies, which are available. And new brass can still be found as well. Although it can be reformed easy from several readily available options.

Edit: According your serial number, it was made between 1896-1897.