They have it listed, worth an email or call to ask.http://www.gun-parts.com/peepsights/
Winchester No. 88-A is what you're looking for. You need the rear of the receiver that has the dovetail cut for it. Thanks for your input and I'm outta luck. No dovetail cut in the rear of the receiver and no threaded hole in the rear of the bolt. On to the next project.