so the dogs are:
- Maschif (evolves at level 30) and can be found early in south province area two.
- Fidough (evolves at level) and is the earliest dog Pokemon in scarlet next to the pond below the lighthouse.
- Rockruff (evolves at level 25) and can be found early in south province area two.
(also later in the game there is a wild tera psychic rockruff if you want.)
- Growlithe (who evolves via stone) can be found early in south province area 3.
- Greavard (who evolves at level 30, nighttime) can be found early in south province area 1.
- Houndoor (who evolves at level 24) can be found early in south provence area one.
- Poochyena you will have to transfer him.
- Snubbul you will need to transfer.
- Entei as you stated.
- Gouging fire.
Then there are they Eevee's, which I I had to say one of them's a dog I would have to say Jolteon.
I would recomend the team:
Growlithe / Arcanine, great for Katy, Brassius and Grusha.
Greavard / Houndstone, bulky guy that can sweep rime and Tulip with last respects.
Rockruff / Lycanroc, any form will do, sweeps Larry with rock type attacks for his flying team and his normal team with close combats.
Fidough / Daschbun, another tank for Mela except fairy resists fire, deals with Giacommo with play roughs.
Houndoor / Houndoom, a physical attacker that can set-up with nasty plot and priority sucker punches.
Entei, can set up sunny day to help Arcanine and Houndoom while finishing below half Pokemon with priority.
If you do not want entei you should choose a dog-like eeveelution or Grandbull
