I've seen one or two of the Lafayette HA250 amps on Ebay over the past year or so.
Another possibility is the Knight TL175 which also shows up occasionally. If anybody will admit to having one, the old Sonar BR21 should also work well as long as you watch the drive level. Okay, so, that dates the time of my pre-ham radio activity! To their credit, the FCC has made Ebay be more careful of amplifier sales, so you don't see nearly as much of the CB trash amps there as was once the case. I'm sure some are there disguised one way or another. For the ambitious builder, when the novice power level was raised to the 250 watt level, there was a sweep tube linear in QST and in a few editions of the Handbook. I think it was in the late 70s or early 80s, and ran a pair of 6kd6 tubes. I was running a Yaesu FT7 at the time, and considered getting a friend to help me build one, but we never got around to it. Mike Duke, K5XU American Council of Blind Radio Amateurs