I have an A7 and a BMW R1100R both insured with Ebike.
When I bought the BMW I thought it would be simple to add it as a 2nd bike to the exisiting Ebike policy, but it turned out that the A7 is on Classic cover and as a "modern bike" the 12 year old BMW had to be seperately insured. It also transpired that the Classic cover doesn't attract No Claims bonus although I was eventually able to get a concession on that from them.
Not an ideal situation but from memory the premiums were £65 for the A7 and £110 for the BMW, so I suppose adding another classic would get it to around £230. In comparison Carol Nash @ £203 sounds reasonable.