First Rule of Layout Building: NEVER pay list price!
I did a quick check at Trainworld/Trainland. A quick check shows that #5s are a$100 and 40" straight are $20. It is worth spending a little time browsing the advertisers on the Forum and in OGR and other sources.
The last #5s I bought I got on sale for $60 each. Recently I bought two of their plate girder bridges -- $30 different.
Jan
PS. TW/TL has sales over every holiday and reasonable shipping.
PPS. Like your inclusion of a ferry.