nice looking bike. I am not familiar with the Alpine name are you and the bike in the states? I doubt the biopace rings are aftermarket as the other conponents look the proper age for biopace.
Alpine my be a catalog brand from some place like Bean, or REI, (I did say like I know REI has there Nouvara brand and Bean used to private label C'dales)
as for value depending where you live a clean Sport LX bike with a ChroMoly frame (it is ChroMoly yes?) would be $200 or so.
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“One morning you wake up, the girl is gone, the bikes are gone, all that's left behind is a pair of old tires and a tube of tubular glue, all squeezed out"
Sugar "Kane" Kowalczyk