No, Harbor Freights not going to carry something like that. You can get them from most metal detector dealers. Also KellyCo, or any number of other on-line md'ing dealers/catologs.
Once you get one, you might consider doing a modification like this: Get a hip-mount set up, and fashion it to be an extension of your scoop. That way you can scoop one handed, without even stooping/bending over. Or to get an even stronger arm-mount, find yourself one of those pistol-grip mounted canes (like they make for semi-handicapped people). Those would be stronger yet to be able to take the stress of digging. Here's a pix of mine. Kind of hard to see, but if you look close, you can see how I added the cane/arm piece. I also added a brace bar to keep the scoop from bending back with stress. Some of the more expensive scoops come with that back-brace already on there.