For routes over oceans, are slide rafts fitted with first-aid items, food, water, radio, etc?
(Source) A Boeing 747 raft survival kit.

Typical content does include nonperishable food and bagged water—

Base kit:


  
  Survival Manual
  Flashlight, w/Lithium Batteries
  Knife Assy., Utility
  Signal Mirror Assy.
  Sea Dye Marker
  Raft Repair Kit
  Whistle Assy.
  Water Package Assy. (4.23 fl. oz. per pack)
  Bailing Bucket
  Sponge
  Lip Balm
  Adhesive Bandage, 1 in (16 per box)
  Bandage Compress, 2 in (4 per box)
  Bandage Compress, 4 in (1 per box)
  Triangle Bandage, 40 in
  Adhesive Tape (2 rolls per pack)
  


Renewal kit:


  
  Sea Sickness Pill Packs (12 tablets per pack)
  Day/Night Flare
  Water Purification Tablets (50 tablets per bottle)
  Antiseptic Swabs (10 swabs per box)
  Ammonia Inhalants (10 vials per box)
  Burn Compound (10 tubes per box)
  Eye Dressing Packet
  Candy (Sucrose) Rations (10 candies per pack)
  


It's the crew responsibility to gather the kits.

They're located near the exits either in closets, ceiling compartments, attendant seat stowage, or overhead bins. Exact location varies by plane and airline.

Axes, first aid kits, ropes, fire extinguishers, megaphones, etc., are also stored in the same locations mentioned above.