I've owned four KLR 650's and never had a problem with the Doohickey, all were in the 1000 to 12,000 mile range when I purchased them. I can say that the 1995 model that I owned with 12,000 miles on the bike when I purchased it the Doohickey was about 1/2 worn through and the spring was broken, the others showed very little wear, but the springs had no tension in them. It's a inexpensive fix so I would personally do it from what I have seem on my bikes.
I had Kawasaki City in Irving do mine, I stopped by and talked with the tech, he gave me a time he could do it. I rode there on that day, he did it in less then and hour and charged me somewhere around $80.00, I had the Doohickey all ready that I had purchased on line. He didn't replace any gaskets as they came off all intact and were reusable. Kawasaki of Grapevine wanted to charge me around $200.00 to do the job and that's with me furnishing the parts, plus they said they would have to replace the gaskets as they would even consider them even if they were good.
Kawasaki City is more of your mom and pop place and not caught up in the big time mega dealer, all though he probably sells more then the other local Kawasaki dealer around, plus the oldest Kawasaki dealer around. They don't have a lot of bikes setting around to be repaired either, if you have a problem it gets handled right quick, I'm sure if your bike need parts that need to be ordered then longer repairs are to be expected.
John