Yes, they do make unfiltered pipes. The Grabow company is in Sparta, NC (I live in Winston-Salem).
I was working on a story about Sparta a few years back and got to take a tour of the Grabow factory. I was quite impressed with the craftmanship and quality, and the tour really changed my perception on Grabows. The original owner's grandson now runs things and he's a great guy. After the tour I notices two racks on the front wall just inside the door; one group of pipes was filtered and the other was unfiltered. I asked if I could buy one and the owner let me take my pick, for FREE! It's a nice bent brandy with a goldish/amber acrylic stem.
He explained to me that though they make production pipes, when a pipemaker comes across a good piece of briar he/she is allowed to make a nicer version of whatever they want. They use bulk ebauchons. The grain isn't the most spectacular (hence the dark stain on most of their pipes), but the briar is good quality (but I'm not sure where it's from).
Now I've never seen these pipes for sale anywhere outside the factory. And, unfortunately, their Website is not exactly up to today's standards. I swear they could be selling these as Grabow specials online and making some pretty good cash.
It's hard to even find a Grabow anymore as most B&Ms don't sell them and pharmacy's no longer carry them. So I don't know who their customer base is. But if your interested, I bet you could give them a call and see what they have. If you're ever in Sparta stop by and ask if they can show you around.