Unison Models
I am quite familiar with the Unison saxes. I represented them at Trade shows from 1996 to 2004 and have sold quite a few out of my store over the years before transitioning to the Hollywoodwinds models. For the record:
The 7002L was the standard model alto. Clear lacquer, no engraving, ribbed construction, tilting spatula, high F#, blue steel springs. The 7002B was the same horn with a black nickel plated body and neck and clear lacquered keys
The 5002L was a budget model with post on body construction. Some had high F# but I recall most did not. No optional finishes.
The S300L was the pro alto. Gold lacquered body and keys, gold plated neck, engraved bell, ribbed,F#,blue steel, etc.
S300GG-gold plated body,neck and keys
S300BG-Black nickel plated body, gold pl neck & keys
S300BS- " " " " ,silver " "
also available as SS, SG,etc...
A2000-Custom model precursor to the Goodson model
The 6003 was the tenor equivalent of the 7002
The S400 was the tenor equivalent of the S300
The T2000 was the tenor equivalent of the A2000
The 5005 was the only bari model
9001- standard soprano, fixed neck
8001- standard soprano, two necks
S100- pro soprano, two necks, high G on later ones
S200- curved sop (I set one up and presented it to Benny Carter!)
Regarding your search, Nolzman. The 7002 is a far better horn than the 5002.
In many ways, I even prefer the 7002 to the S300 series (they are totally different instruments, not just an engraving difference) For me, the 7002's were darker and more centered, the S300s were brighter and a bit more flexible (pitch and timbre) which many other players preferred.
The key layout is great, the scale is excellent, the padwork on most was very good.