FWIW, the one shown on ebay looks, from memory, JUST like mine, which I bought used from a dealer here in Japan, where the Cello equipment had quite a good market (and continues to have a healthy secondary market - I have seen three go past the used market in the past 4 months and the lowest offer I have seen is just north of $1000 (store), the other two went for $1300 (store) and $1550 (auction)). I will check later tonight against mine to confirm and post again. FWIW, there should be pictures on Google Image if interested in chasing more pics down.
They still have quite a following in Asia based on the quality of the 59 step attenuator (from 0 to -50db in one-step increments then to complete attenuation in another 8 steps), which is supposed to be among the best made. I personally had a problem with the frequency extremes being "thin" but I can say that the midrange was as transparent and detailed as I have ever had the pleasure to listen to.
The Etude was originally sold some 20 years ago (first sold in 1986 I believe). FWIW, specs were as follows:
input impedance: 10k ohm
output impedance: 0-10k ohm (though the one-page manual specifically states 100k ohm amp input impedance preferred)
Size: 24W x 10H x 25D (in cm)
Jacks: 4 RCA inputs, 1 set out
From what I have heard and read, the stuff made by Mark Levinson under a name other than his known which may or may not be re-badged Chinese equipment is Red Rose Music equipment.