Your first hurdle will be your "collector" bony fidos.
Just like Section 1, for Section 7(1) and 7(3) you must have a "good reason" and: "I'd like one" isn't good enough. 7(1) at home can ONLY be as "part of a collection" (No discretion, it is in the Primary Legislation.) and 7(3) is not allowed for recreational shooting or competition.
Before the fuzz will give you either you must demonstrate that good reason. For a start you will probably need to be a Full Member of an organisation like the HBSA.
If you can make the Trafalgar on Saturday, the HBSA are holding a Section 7 Exhibition in the Army Target Shooting Club hut. There you will able to get good advice on Section 7 and what is involved. You MUST have your FAC on you.