I'm looking for inexpensive, drop-in replacements for my 1996 Ranger extended cab's OEM 6x8 speakers. I have a Kenwood x498, 22W RMS/ch.

I've found one speaker model from Kenwood and one from Clarion that look like they came off the same assembly line:

Clarion SRG6833C $37/pr. (link to Amazon)
Kenwood KFC-C6865S $36/pr. (link to Amazon)

The woofers look identical. The Clarion is a 3-way vs K's 2-way. But the Kenwood is 3db more sensitive. And my 60-years-old ears probably can't hear a supertweeter.

Any experience with these or other 6x8s in this price range? Thanks!

Crutchfield.com & find the cheapest Pioneer 2 way (coaxial) 6x8's they have. If they will never be amped, best you can do, for the price. If you want to spend a little more for better quality and response from the ~22 watts RMS (questionable), look at the cheapest Infinity 6x8's they have. They are ~3 ohm and 93db sensitivity and will make very efficient use of the available power. If you have a regular cab, just get 1 pair, tape off the rear speaker leads, fade full front. Those rear speakers aren't adding anything good to the soundstage.