The .22 barrel is a good example of a genuine Webley barrel of the period as supplied as an aftermarket spare. These were supplied by Webley without being numbered .
The .25 barrel is a genuine Webley one, originally supplied with a gun that carried no. 674 as the last 3 digits of it's serial number.

In all it's a good example of a genuine assembled set , as good as most people are likely to meet nowadays