Hi Amin,
This might be a starting point: http://www.rlm.at/cont/archiv01.htm. Towards the middle of the page, there is a table listing RLM, FS-595b, FS-595a and other colors.
Additionally, you might have a look at http://scalemodeldb.com/paintcharts/vallejo
Select Federal Standard at the top, in the Brand column and you can manually compare the colors to Vallejo.
Hope this helps!
Cristian