I set up a backup plan for this sort of thing at the beginning of the campaign - in fact for all the campaigns I have run. My characters kept hearing rumours about a mythical site somewhere in Sanos Forest where a 'powerful sage and cleric of the Old Ways' lived. Then, when a character needed to be raised/resurrected etc, there was to be a small side quest where they could go into Sanos Forest and find the sage/cleric.
I haven't used it so far, but was going to make the sage/cleric some sort of Fey - somewhat akin to Tom Bombadil - who would help them in return for a 'small favour'. It would then be a recurring NPC should another character need raising, or if they needed to find out information.I chose Sanos as it was fairly central, so they could reach it quite easily and not slow down the campaign.
I always keep such a device in my back pocket - helps keeps things moving and makes the characters work for their raise/resurrection, rather than a free pass.