All week a Radio Systems TR6000 Transmitter was on auction at eBay, and as second bidder my offer of $103.00 stood most of the week.
TR6000 is adjustable 0-10 Watts for TIS and carrier current, new models costing above $2,500.
This afternoon in the last hours the bids climbed into the multiple hundreds so I tuned out.
The version shown was an earlier model with controls on the flat wide surface, replaced more recently by a version with controls on the narrow end panel for conserving rack space.