The price I would consider paying for a used stainless steel Encore frame in excellent condition would be from $275 to $300; maybe 325 for a Pro Hunter frame.
The wooden buttstock doesn't add that much to the price; maybe $35.
The frames and barrels in gun shops in my neck of the woods seem to be way overpriced; I would never buy one there. I saw a stainless steel barrel in Cabela's "Bargain Cave" and, if I remember correctly, the price was over $300. What a crock; I've picked up multiple Encore and Contender barrels, stainless steel and otherwise, in new to excellent condition (including a couple of stainless steel Pro Hunter barrels) for in the $155 to $215 range with many including extras like bases and rings. Shop the forums like Graybeard Outdoors and auction sites and, if you're patient, you can snap up a good deal.