Correct, Merkur is the only company I know of who still makes an Adjustable razor.
They make three models (the Futur, Progress, and the Vision), but the Vision is best avoided as it is a gigantic razor, and also requires one to dissemble it to clean it frequently. There have been several reports of the razor breaking when people attempt reassembly after cleaning.
I've had the Futur for awhile and think highly of it. I haven't tried the Progress or Vision, but I have a used Vision on the way. I've watched the disassembly video and it doesn't look half bad to deal with. The Progress is interesting - I'll probably get one and have it reworked into a Mergress (courtesy of member Mer) sooner or later.
Be sure to consider the vintage Gillette adjustables, as well. They're plentiful and prices are fair. If you shop at eBay, be careful not to spend too much. The auctions sometimes get bid up too high and some of the BIN razors are at ridiculous prices.