It looks like an early 80's Le Tour to me. Steel wheels, lawyer lips, turkey wings etc. - but in is original form, a surprisingly decent riding bike. (Pretty nice looking too.)
The substitution of the crank however, really detracts from its value. If all that remains is well preserved and relatively rust free, I would say about $40-50.
(Not a bad deal at that price, if you have some spare crank sets decorating your garage walls - Otherwise I would pass and look for a complete bike.)