I certainly don't have more info than you, but can say that Elburg bows are rather rare on the market. His shorty longbows are real gems and I would love to get one, but any of his bows are seldom for sale. With that the case, it would be really tough to put a value on those bows. Your bows seem really special and even harder to appraise.
I believe insurance for these is going to be subjective unless you can get a written appraisal from a recognizable dealer, collector, historian, etc. Who the heck has those creditials today?
Knowing insurance companies, they're not likely to fairly reimburse a lost/stolen Elburg.
It looks like you are new here, so welcome. Many of us would really like to see pics of your bows if you can post. If not, send me some pics and I will post them here for you. We also may have more Elburg fans here that provide lots more. Good luck.
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