Rock tomb ranges at level 13 (ranges in brackets are for growl ranges):
12-21 (8-5)
Tackle:
5-10

Crucial Defense IVs at 13 according to possible fights.
If faster:

-0-6 defense, 24+ SpA, 29 HP (24+ IV)
T1: Growl, RT to 16.
T2: WG (12), Harden/Block
T3: WG (12, Oran to 23), Harden/Block
T4: Mud-Slap (5), Tackle to 10
T5: risk a miss (40%), get the range (17-20).
Otherwise, just go in at full and do 2014 strats with t1 growl.

+22 defense or more, 24+ SpA, 16 HP
T1: Tackle (1), RT to 2
T2: Potion, tackle to 16
T3: Harden/Block, Water Gun (12)
T4: Harden/Block, Mud Slap (5)
T5: Tackle into torrent, WG (19)
meh
(work in progress)