Wipe them down with some acetone, which is available from Home Depot or Ace Hardware. When you put them back in, use some motor oil on the O rings to make assembly easier.
Fuel injector seal kits with 2 O rings and a pintle cap (Borg-Warner P/N 274081) are available at Pep Boys auto parts. Cost is about $2.74 per kit. The pintle caps fit either injectors with a pin sticking out the injector end or 4 with more tiny holes in the injector end. The following are listed at the Borg-Warner site (
http://www.borg-warner.com ) as being resellers of Borg-Warner parts:
http://www.partsplus.com/ or
http://www.autovalue.com/ or
http://www.pepboys.com/ or
http://www.federatedautoparts.com/
Most of the links above have store locators for find a store in your area.