Just posting a brief note to perhaps save somebody else some research effort.
This weekend, at the Pacificon hamfest, I acquired a Telonic 4053A RF sweep generator. It's a nice, compact little box with three bands (0-450 MHz, 450-900, and 900-1350), sweep widths from 200 kHz to 500 Mhz, slide-switch and vernier attenuators, a bunch of crystal- controlled frequency markers, and rated output of +7 dBm.
Naturally, I wanted a manual. Initial searches came up empty, with little information other than that this is a "special model" built to FAA specifications (and mine has an FAA stamp on the back). A few postings from years ago suggested that other buyers of these surplus sweep generators also failed to find manuals.
After digging a bit deeper, I seem to have lucked out. At KO4BB's web site, I found a couple of Telonic manuals in the "miscellaneous test equipment" section. One was for the Model 1205 sweep generator, which appears to be the same device - identical physical appearance, and the internal layout seems to match mine. The 1205 is described as being able to take a set of up to 7 marker-generator crystal-oscillator sub-boards, and I suspect that the "4053" may simply be a 1205 with an FAA-specified set of marker boards and a front panel silk-screened accordingly. There may be other differences but, if so, they don't seem to be profound ones, and the 1205 manual and schematic and alignment procedures should still prove useful.
My new acquisition seems to work, making the $20 I paid for it a real bargain.