If you have items with specific importance or value, then you need to get insurance that covers that. Not some generic cheap insurance. You need “Agreed Value” insurance.
You may pay a little more for it. Otherwise pretty much all insurance companies use the “market value” or “Cash Value” at the time of the loss.
I insured a 60 year old car through Hagerty for an Agreed Value of $22K. Cost me $150/year and included liability insurance. I suppose I could have insured it through State Farm as there is documentation that the vehicle and others like it have sold for that amount recently but the amount could fluctuate depending on the market.