s the reserve price able to be estimated from a recommended retail price for the item?
One thing typically has absolutely nothing to do with the other. It's completely up to the seller what the reserve is. Unless the seller is a complete bonehead, the reserve should be FAR below normal retail.
For instance, if something is shown as having a usual store price of $60, can I guess what the reserve will be?
Impossible to say with the information provided. Companies can play games with retail prices and actual sale prices.
Is shipping from USA to Europe extortionate?
Not enough information. Shipping a feather would be cheap. Shipping a boulder would obviously be much more expensive :-)