Finding a 3P rifle in good shape under $1000 with all accessories will be difficult, you may be lucky to locate an older Anchutz model 1413/1813 or may be a Walther KK Match.
However if your are serious about shooting 3P match, you'll need to budget a few hundred dollars more for items such as sling; butt hook; spare sight; hand stop...etc, best bet is to visit a target shooting club and speak to experienced shooters, more often than not, some may have used equipments they want to sell.