Search ebay or do a Google image search for the signs you're looking for, copy & paste the photo into MS Word, Wordperfect or whatever you use.
Re-scale to proper size and print. Use the largest photo available for the best resolution. Make sure your printer is set for best qauality printing also.
http://www.scalemodelingbychris.com/page_two.htm also has a selection of signs with adheisive backs.
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