Please don't bypass paying for the real thing.

Please don't recommend cheap imitations.

hhp

>is there an identical alternate to type: Interstate which has more weights?

No

An Interstate clone with more than eight weights? I guess you'll just have to draw one yourself. How hard can it be, after all? :-|

There are other multi-weight faces based on the Highway Gothic design, or related, e.g. Expressway and Blue Highway (from Typodermic) and Clearview (from Terminal).

Clearview is not all that similar to Highway Gothic, although it is certainly intended as a potential replacement for Highway Gothic.

Yes, that’s why I said “or related”, by which it is understood that they belong to the same genre of being designed specifically for highway signage.

There is also Transport, but it only has two weights.

Also Wayfinding Sans, http://www.myfonts.com/fonts/fdi/wayfinding-sans-pro/