That's a dangerous thing to do. Problem with Webley is they made a lot of models, and a lot of varients of each. You may find your collection growing quicker than you thought it would.
If you don't already have the books, I really recommend Gordon Bruce's Webley Air Pistols, and Chris Thrale's Webley Air Rifles. Also Dowell's The Webley Story, Gordon Bruce's (again) W&S Automatic Pistols, Stephen Cuthbertson's World Wide Webley, plus the Webley Solid Frame Revolvers books. You may find your interest goes beyond Webley airguns (fencing musket, other guns, machine parts, vehicle jacks, electric fans etc etc etc...) Happy Days!