i am no mechanic but if you have original wires with 175k on them and plugs with 75k i would assume that is your problem,the wires are probly so dried rotted and plugs probly look like charcol,when it is dark out side spray some water on the coils and wires and you will probly see a pretty good light show.
I understand all of that but this has been an issue for about 5 to 6 years. it isn't a huge problem and it isn't happen constantly. it tends to happen when on the highway at around 70mph or so, and trying to accelerate. at lower rpms. I had the plugs and wires checked a year or so ago, and they were fine then. but as i said this has been going on much longer than that. it doesn't have that lake of spark jerkiness it seems more like lake of gas kickups?
Change the plugs and wires. This may not be the problem, but often diagnosing and fixing operating issues is nothing more than a process of elimination. Pick the most likely candidate, eliminate it, and move on to the next likely candidate.
The most likely candidate for you is plugs and wires. Followed by ignition coils. Followed by fuel injectors. Followed by .......