[Nathan Slingerland]

Modern component values are somewhat different than the pre-WW II versions. Just get the version closest to what it's supposed to be. Most of the components are pretty forgiving in terms of tolerance (say +/- 20%).

For .05uF you can replace with .047uF:
http://www.radiodaze.com/axial-film-047mf-630v/

For .25uF you can replace with .22uF:
http://www.radiodaze.com/axial-film-22mf-630v/