First is to understand how stain works. See the brighter orange? Thats the color you are shooting for. The darkness will replicate itself on any rougher, more porous or damaged areas. Penetrating stain will give you a nice clear, but lighter color than a heavy wiping stain. Finish with an oil of your choice. Some woods, like walnut and oak, take on a rich orange hue when just oiled or stained with a "natural" stain.
Do you have a Diamond Vogel paint store local? If so ask them to sell you an ounce of 680 Dark Yellow NGR dye. A small glass or solvent proof plastic jar would be an appropriate thing to take with you and will increase your chances of getting some.
Mix it in with some tung, teak, or boiled linseed oil and apply. The dye is VERY STRONG so add a small amount and test it on a smooth sanded part of the under side of the handguard. A small amount is like one drop of dye per ounce of oil. Each subsequent coat will deepen the color slightly. If it looks like you need more dye, add another drop.
Use some whiting to remove any oils currently in the handguard. Then sand with 220 grit, with the grain until uniform. Apply a couple coats of oil, hit it with some 320 grit, and apply a few more coats of oil. Let it cure for a week or so, then buff it with rottenstone and a touch of the stock oil on a soft, lint free cloth. Denim actually works quite well. This will give you that deep soft lustre.
