You could cut the contour of the logo. It would still look like a sticker, but would look better than a big rectangle. You could use casting wrap vinyl and so it takes on some of the texture.

You could paint it on, or draw it on with markers.

You could hire a metal manufacturer to specially stamp the logo onto metal products.
That's not very cost effective though.

You could have the company logo changed to a giant powder coated aluminium rectangle, that way no additional work would be needed.

Clear stickers don't have the saturation for that.

As for the cheapest method, think on it a bit. If you have a printer and a plotter...
You should know other solutions if you are offering print as a business.........

Should clarify, I do not work for a printing business. I am an in-house designer for a manufacturer.

Experience is in print, so that's why I could only think of printing on a sticker. The result is not quite what I was hoping for.

As someone else mentioned, we could digitally die-cut to eliminate a lot of the clear sticker (and perhaps use a sticker with a matte finish)... was just wondering what some other options are.

Silk screening is the first thing that comes to mind. But, it won't be cheap.

Printing and then cutting out the letters may also work.

I haven't explored it, but in my photography magazines I always see ads for companies like this - http://imagewizards.net/ - that print on aluminum. You may want to see if they offer anything that could work for you as well. I've never seen one in person, so it may not be what you are looking for, but it's worth a shot.

If that aluminum print is like all the other similar aluminum prints out there,
- white is silver (the metal plate itself)
- they use an anodized aluminum print process that is very difficult to fabricate after the print is made, and has to be flat to have the print made (anodizing cracks if bent)
- they have serious size constraints.
- They don't print on YOUR supplied metal.
- These are NOT cheap.
- Some of these are dye sub on aluminum plates rather than anodized. The fact these don't take outdoor sunlight makes me wonder if they are dye sub.

Each process has it's place and I've used both.

Quite honestly there are only a few places that actually make the anodized prints. But there are a lot of brokers.

The cheapest method is to find someone who can die cut that in printed or sign vinyl for you, accurately.

There are a few more expensive options such as cutting the pieces in plastic, painting them and adhering them with VHB tape or more simple options such as making the logo on a tastefully intentional branding plate (pay attention to their negative spacing rules).

Decal is an option.