Source for roll out shelf?

Need a robust, low profile slide out shelf for a closet shelf to hold
something heavy. Need to gain top access after it slides out. Picture
a heavy metal box like a tool box to sit on a shelf with only 12 3/4
inch clearance and the box is slightly taller [with lid closed] than
10 inches. Weighs approx 18-25 pounds.

Just need a low profile shelf that attaches to a particle board shelf
[that'll be a challenge, too] sit the box on it. When want access,
simply slide/roll the box out from under the above shelf, open up, and
gain access.

May have to attach a metal plate [right angle to also attach to wall?]
to the particle board to make it strong, then attach a slide to the
plate. Because with the shelf fully extended there will be a lot of
cantilever force on that shelf board.

Where to find such items?