Here's Cacturne's base stats:
HP: 70
Attack: 115
Defense: 60
Sp.Atk: 115
Sp.Def: 60
Speed: 55
Total: 475
Also, is it possible to check IVs pre Final 4 in Emerald?
EDIT: Apparently not, fortunately there are calculators out there. From the looks of things, this Quiet Cacnea looks quite promising, so I've started EV-training it. (It was bred, FYI, so things are
slightly wonky in that regard.

On the plus side, it starts with a higher Happiness right from the get-go.)
Cacnea (Lvl. 20)
Current EVs: 20 HP/61 Sp Atk/0 Atk
(20 HP/0 Atk/0 Def/61 Sp Atk/0 Sp Def/0 Spd)
Current IV ranges:
HP 25-29
Attack 17 - 23
Defense 15 - 19
Spec. Attack (x1.1) 15 - 19
Spec. Defense 15 - 19
Speed (x0.9) 5 - 14
Not too bad, considering I have almost no control over the process in Generation III, and that both Pokemon used for breeding had rather poor IVs to start with.
