ROMAC, most any gun sound enough to shoot safely and reliably will be worth near $1000. Sleeved barrels,and for that price I'd bet you are talking sleeved, not lined, give all guns a big whack. Due to the variability of sleeving work, it is hard to pin down exacting values. Post detailed photos and/or take it to a skilled double gun person. The more information, the more we can pin it down.