I think you're on the right track.
There are three basic types of swim currents: 1. jets, 2. props & paddles and 3. hybrids.
You've already swam in a jetted swim spa. A lot of companies make these: CalSpas, PDC, Master Spas, Sunbelt Spas, Alps, Diamond, Dimension One, Dynasty, Royal, Spa Manufacturers, Sunbelt, etc. They all move a small amount of water very fast. They are all sold through local dealers. They are great for recreational swimming, but not ideal for a 10-30 minute swimming workout.
Next there are the counter-current pools that use a propeller or a paddlewheel. The most well-known of these are Endless Pools, SwimEx and Bradford Products.
Endless Pools is known for the quality of their swim current. They are used by a lot of Olympic swimmers, college swim programs and professional triathletes. They have a modular product which sells for about $20K with a basic installation runs around $3,500. They also have a single shell swim spa with an area for sitting and relaxing in your price range and a steel framed product (with no seats or jets) that starts at $12,900. Endless Pools sells through dealers and also direct. Customers can use their own contractor or one of Endless Pools' 300 factory trained installers.
SwimEx also has a great swim current. Using a paddlewheel they create a wall of moving water that spans the width of the pool 18 to 30 inches deep. They have several models for home installation starting in the high $20Ks. One of their models, 500S, does have a built in area with jets. Installation is either by your contractor with advice from their field representative or their factory trained installer.
Bradford Products makes a stainless steel swim spa, but I don't know much about them.
Finally there is the hybrid. Master Spas makes the H2X, which is also branded as the Michael Phelps Swim Spa. It uses a small propeller to makes a current that is larger than the jets, but smaller than the counter current pools. They sell through a network of dealers. It is a well built spa, however, I personally found the swim current wanting. There are only 12 speed settings (compare to 50 in the Endless Pool and 99 in the SwimEx). Also, to me, the swimming in it was not relaxing. I needed to spend more physical and mental energy staying centered in the stream rather than thinking about my stroke or other things.
Michael Phelps swim spas list for the $40s and $50s, but if you go to one of their traveling road show blowouts, you can get a floor unit without the Michael Phelps branding for 50% off.
On to servicing. If you find a local pool and spa store that you trust, they will most likely be willing to service any of the above swim spas. Most of the thing that go wrong (water chemistry, leaks, bad pumps) can be handled by any good local dealer. If it is a problem with a unique system of the swim spa, the manufacture will work with the homeowner or local dealer (even a dealer that does not distribute their product) to fix the problem or send in a specialist.