I've a Lyman globe sight on my 336 on standard front ramp dovetail (with a Williams rear sight) and a anschutz globe front sight on my 39m which has an alloy adapter mounted to the front ramp screw holes- the anschutz dove tail runs parallel with the barrel so needs an adapter.
Mine came on the gun when I got it, midway sells them, think their Williams brand. Mines alloy so easily modified, my sight was canted slightly- bit of filing and adjusted base so sight sits straight now.
The Lyman globe (which is a lot smaller than the anshutz) works well with the Williams foolproof sight. With the Anshutz globe I have a central sight with adjustable Parker-hale apature