In another thread it was mentioned the Selmer USA Omega alto.
In the 1983 WWBW catalog
Omega Alto - Retail $1500 / Mail Order $1030
Super Action 80 $2300 / $1495
A retail difference of $800.00 US
and a mail order difference of $465.00 US
I also had an earlier NEMC catalog from fall 1981 which had Selmer mk VI, mk VII & SA80s listed but I can't find it.
I remember the newpaper For Sale Ads of people selling mk IV, mk V and mk VI's
typos back then.
So I figured there were multiple models of those horns ... so VII must be better than VI and V & IV.