Currently on ebay is a lithograph of the Martin X-23 PRIME (Precision Reentry Including Maneuvering reEntry) subscale lifting body, a mid-1960’s program to build small test vehicles for the full-scale X-24A lifting body. This depiction shows it without the “bump” on the forward fuselage simulating the contours of the cockpit canopy. The seller is rather optimistic with a $1875 Buy-It-Now price, although he will consider offers.

Another copy of the same lithograph, along with a lithograph of an orbital HL-10, sold a few months ago for less than $400. That was too rich for my blood for two lithographs, never mind nearly two grand for one. Shrug.  But at least the listing provides a fairly decent photo of the art. I *believe* I’ve only seen it reproduced in B&W.