I didn't buy an STI group in above avg condition for $300. If I had to do it over, I would have.
I'd say $200-$250 if immaculate and cables included, down tube shifters.
Add $100 for STI's.
I assembled the same group individually:
STI's: $106 but included a bar/stem combo (Bike Wagon)
crank set: $41
FD braze-on: $24
RD: $44
Levers: $34
Never did get the calipers, still looking but won't pay $50.
If you're thinking of selling that group, we can talk.
I have the OEM 600 group for that thing....