Hi Alan,
I've been an insurance broker for almost 30 years now, so can give you a professional answer to your question. Unfortunately insurance is one of those subjects where many feel they know what they are talking about based on personal experience, without actually having much of a clue. No offence intended to any posters on here, but the bane of my life is "well my mate said.....".
Short answer to your question is no. Most policies have a single article limit whereby you would specify any item that is over the limit. Typically the limit is £2500 although this varies between policies & isurers, so check your schedule. It's probably unlikely that any single kit will exceed the limit.
Having said that, it could be argued that your stash represents a collection, and that the total value could exceed the single article limit. In that case it would be worth speaking to your broker/insurer and disclosing the information, they will tell you whether the collection needs to be specified.
rant mode on
The biggest issue with insurance is that the majority of consumers don't read the paperwork that is sent to them and just assume they are covered. Insurers don't avoid claims unnecessarily, with the amount of regulation from the Financial Conduct Authority (in particular the Treating Customers Fairly initiative) this just doesn't happen. What insurers will do when you make a claim is check to see if you are covered. Again, it's down to the policyholder to know themselves what they are covered for by reading their policy.
Unfortunately many people nowdays are buying insurance based purely on price rather than the cover provided. Often people go on comparison websites and pick the cheapest option thinking that insurance is all the same. As with anything in life, you get what you pay for, or as I often say to clients, pay peanuts get monkeys. Although brokers tend to charge more, the extra is paying for a professional with years of experience to give you advice, rather than a bloke in an offshore call centre reading from a script.
rant mode off