Also most lower cost stamping kits have single punch letters/numbers and you'd need to align them perfectly. Not sure if there are better ones where you can install them all in a block. Sort of like setting the old lead type they used for newspapers/printing years ago. If you can find some old letter and number slugs that might be a cheap way to go. Fonts might be hard to find in the Ludwig style though? You'd need to research it a bit. Anyone know how Ludwig and others stamped the number plates back then? Would be cool to know. I wonder if they had a crash number type machine that spit out numbered badges?

That's pretty much what I'm looking at. I would practice on a piece of Metal or aluminum first before trying it on a badge.

I'd like to know what size Ludwig used for there numbers.

Do you have any badge numbers there you can measure? Most type sizes are defined in pica's. 6 pica's per inch etc... You can measure the height and convert that into pica's. Unless you have a ruler with a pica measurement on it. Some of the better metal ones have it. So if you shop for type it may be pica's if it's old school stuff. If you don't have a badge maybe someone here can measure one for you.

Here's a conversion chart.

http://www.asknumbers.com/InchesToPicas.aspx

***edit to add......could be in "point" sizes too those are smaller than picas. Sorry I'm rust on my points and picas. :p