The numbers are made to look as if they were stamped by a handheld rotary rubber stamp similar to or the one described in this patent: http://www.google.ca/patents/US3955499
Still looking for the base font for the numbers.
Don

More finished sequential numbering and other info can be produced from a mechanical auto-incrementing numbering device used on letterpress equipment. Sometimes called "crash numbering" or "crash printing."
Don

PsyOps has a sequential number font but it is a different design. Ssee Crash Numbering http://www.psyops.com/shop/typefaces/crash-numbering/
Don

Similar letter-forms:
Ingeborg Regular

http://www.myfonts.com/fonts/typejockeys/ingeborg/
Gilbert
http://www.myfonts.com/fonts/t26/gilibert-sc/
New Standard

http://www.myfonts.com/fonts/paratype/new-standard/
don

If you look for a distressed typeface, using the terms Don explained as keyword should give you some alternatives. For example, "N0." is LL Rubber Grotesque: http://www.dafont.com/ll-rubber-grotesque.font?text=N0.

Some digital alternatives, some needing to be roughened/eroded (more):
- 'NO.': Nidex, Sans Culottes, Dogjaw, Warpaint, Canard
- '610242': Indicia, Appareo, Rough Print, 1917 Stencil, 1820 Modern, Matchwood, Etaoin Shrdlu

As for similarity of shapes for "61042", I found Chlorine Serif (http://www.myfonts.com/fonts/victory/chlorine-serif/) and Trola (http://www.myfonts.com/fonts/tipografies/trola/).

To add to Ryuk's exellent list of alternatives for "N0.": PF Fuel (http://www.myfonts.com/fonts/parachute/pf-fuel-pro/).

To make a close match start with Ingeborg or Trola. I already posted the Ingeborg numbers. Here are the Trola numbers
Compress. Make a few adjustments -- particularly straighten the sides on _0_ and _6_.Shift the numerals up and down for a bouncy effect. Semi stencilize and distress them.
Don

http://www.myfonts.com/fonts/linotype/tagesstempel/