Depending on where you look for them that's no mistake, same bolt by both names.
http://www.mcmaster.com/#step-bolts/=j5tpke

Or here's what's called a step bolt and resembles original.
http://www.fastenal.com/web/products/detail.ex?sku=22546&ucst=t

I used elevator bolts from McMaster and while they weren't exactly like the original they are just as functional and no one will ever see them or care.

The elevator bolts I got are dead flat on top of the head and tapered under it. The originals are more like an extra large and low head carriage bolt that is flat on the under side and domed on the top.

Grigg

•1951 GMC 250 in the Project Journals
•1948 Chevrolet 6400 - Detroit Diesel 4-53T - Roadranger 10 speed overdrive - 4 wheel disc brakes
•1952 Chevrolet 3800 pickup
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"First, get a clear notion of what you desire to accomplish, and then in all probability you will succeed in doing it..." -Henry Maudslay-