Hello,
I always find it a bit difficult to date Webley Mk3s who's Ser No are pre-fixed with the letter 'A' as for some unknown reason, Webley used this pre-fix for two separate batches. What we can say, is that yours is a later 7th Series example made between 1968-1971 depending on batch.
I would estimate a complete, fully functional Mk3 in reasonable cosmetic condition to be worth in the region £120-£150. The scope wouldn't attract much of an additional premium, but taken together with the pellets and paperwork might result in an additional £20-£30
To post pictures you first need to register (Sign Up) with one of the internet photo hosting sites such as Photobucket. Registration with Photobucket is free and easy when you follow the on screen instructions. Once registered, you again follow the instructions to upload your pictures from the relevant file on your computer into the Library within Photobucket. Once opened from the Library, you will be able to resize the pictures etc and share them using one of the four options displayed to the right of the screen. Due to resource constraints, we don't post images direcltly into posts, but use a link to the photo hosting site. This is the 'Direct' option second from the top and will be automatically copied when you click on it. Now all you need to do is return to your BBS post, right click and paste the link into the post. When you submit the post in the usual way, the link will appear and when clicked on will take the reader to the picture within Photobucket.
This may seem quite complicated when written down, but really is quite straight forward in practice.
If you have any problems, feel free to PM me and I will be happy to post the pictures on your behalf.
Regards
Brian